For me, the answer has been lots of practice over the years plus lots and lots of patience. Cutting in takes time! (For me, at least.) Like paintguy, I don't use tape; I did when I first began painting, but it quickly became apparent that, unless the two planes met at perfect right angles and were straight to begin with, I was giving myself a non-straight line to follow. Not to mention, unless I followed the joined area perfectly, which I could not seem to do, I'd have many touchups to do anyway. In the end, it was faster just to do the job without tape. Unlike paintguy and like moonshadow, I use an angled (Purdy) brush. The width doesn't matter to me, although I do use narrower brushes for tighter areas. My technique sounds very similar to moonshadow's as well. I also hold the brush so that I'm applying a bit more pressure to the bristles that are applying paint to the actual cutting-in line and less pressure to the bristles on the other side of the brush. This helps to naturally feather paint onto the wall (or ceiling). I just finished cutting in a 30 foot line of wall paint that abuts an angled ceiling. Honestly, really truly, I don't plan to redo any of it. It looks very good! A few more tips: after you've finished an area and have new paint on your brush, you want to paint into the paint that's already been applied, that is, do not paint a section, then start there and paint the next section. Instead, paint a section, then start at the END of the next section and paint BACK toward and into the previously painted bit, feathering lightly into the previous bit. To paint section by section back into previously applied paint, I have found that it's much easier to paint the cut-in line as a whole by working away from the direction of your dominant hand. Thus, since I am right-handed, when I started the cutting-in line on that 30 feet of wall, I started at the right corner and ended up at the end of the job at the left one, while painting each section from left to right. Had I been left-handed, I would have started at the left corner and ended up at the right one, painting each section from right to left. Another tip is that it can sometimes help a lot to find something to rest your brush hand on as you work. In the case of the room with the 30 foot wall, I had the tops of molding to two windows and a double door's top molding. As I painted, I used the molding to steady the side and palm of my hand on the pinkie finger side. We did the wall by painting it first and then cutting in (people usually do the opposite -- cut in and paint, I think). Thus, to keep the paint on the still-uncured wall clean and unmarred, I steadied myself where there was no molding by VERY lightly using the tips of the fingernails of my left hand to stabilize myself....but only if necessary. Far better not to touch the wall at all. Regardless of whether wall (or ceiling) had already been painted or not, if you do have to touch it for any reason, try to do so with the back of your hand, and lightly only. Generally the back of the hand is less dirty than the front and reduces the chance you'll get fingerprints on your surface. When painting anything, I usually have a very wet paper towel at hand. When cutting-in at ceiling height, I usually keep it on the top of a ladder. If I do use it to clean up a mistake, I'll leave that area alone until completely dried and go back and touch up later on. Another tip: to really reduce any difference in the appearance of paint applied with roller on wall or ceiling vs. the cut-in area, after the cut-in paint has dried, I'll follow the whole thing with a small roller. With a steady hand, it's possible to get within a fraction of an inch of the cut-in line. And again, as when using an angled brush to cut in, I apply slightly less pressure on the roller's outer edge. And again as well, I work section by section back into a previously painted section. I also agree with paintguy about painting wall paint on the ceiling. I initially tried edging the wall-ceiling joint precisely. In the end, it was much easier to go a tiny fraction onto the ceiling. I estimate I did it by maybe an eighth of an inch, if that. From floor level, you can't tell at all. Teeny artist brushes -- I now use those only in corners, where two surfaces are not straight, and in cases in which I must not get paint on a surface. Example: I had to cut in with the wall paint around the end of a stained, curved stair tread. I will be using one (along with a regular angled brush) when I paint a vertical piece of floor-to-ceiling molding that separates one of the walls in the room we're painting from a stone wall. The molding on the stone side was cut with a jig saw and follows the curved, natural line of the stones. Thus, I can't just use an angled brush along that edge. Whomever did the job initially painted the grout or caulk or wood fill or whatever it is along the stone (sigh), so now I'll have to do the same. Since I don't want paint on stone, I'll meticulously follow the previous paint job, using a tiny brush. I actually had to do something similar when painting the master bedroom. Went from white walls to a mushroom color. The room has 16 wood ceiling beams set into the walls. Thus, two coats of wall color and 16 beams X 2 (beams ending in two walls) is the equivalent of 64 beams as it were! And of course, because the beams are set into the walls, there were three sides to each beams -- left, right, and bottom. To make it worse, on one wall, 5 beams were over an open stairwall. That part was a bit of a challenge....Suffice to say I am never repainting those walls!

Cutting walls and leaving gaps in areas where there will be a backsplash it's perfectly fine. I see many homeowners posting their opinions and their experiences, but I don't see many counter top professionals or technicians giving their two cents here. I have worked in the countertop in the street for more than 12 years and I have found that there are many different kinds of countertop fabricators and absolutely none of them are looking to do a sloppy job in your house. Nobody makes money out of going back to the same house several times. You have your small shops that will make one kitchen a week, you have your medium size shops that will make one kitchen a day, and then you have your super shops that will fabricate more than 10 kitchen daily. Every template guy will do their job in a different way. Ultimately what all of them want to accomplish is to make a countertop that will look beautiful once the whole project is finished. In most cases the countertop is not the final step on a remodel project. Most of the time there will be tile sitting on top of the granite, and when that is the case you can have gaps up to a 1/16" smaller than the thickness of the tile (1/4"). And if the wall bumps out in certain areas The wall can be cut with a blade or a Dremel tool and the granite slides under this cut. Once the tile sits on top of the granite it completely covers the gaps and the cuts. This does not compromise the integrity of the wall at all. Sheet rock is hanging from the studs and it is not holding the house together. If you have plaster walls then you might be charged extra for the labor needed to have the granite fitted to the shape of the wall.

Any change in plane is to be caulk not grout. Grout will not move with the walls expansion/movement, it will crack. TCNA standards are caulk,

Update: I stopped at the kitchen cabinet maker today. It's a well known and reputable company in my area. I picked my counter top sample actually in his showroom. The counters were ordered through him. He already knew about the mark and that they were coming today to try and fix it. I showed him before and after photos. I explained when you walk right around the perimeter of the kitchen island you don't really see it so I thought it was fine when they left.......BUT the reason is because they dulled the finish. When you enter the room and you aren't standing right at the counter you can see the dull spot. The owner of the cabinet company has been in the business over 35 years and I trust his advice. I'm just not sure if it will matter to me as much in a few weeks as it does today.... He told me I can wait to decide. He sent my photos over to the counter top company so it's documented. He said in a month from now once I am using my kitchen (and my pendant lights are in) if it's still bothering me we will address it. He also said he does a large amount of business with them (about 100k per month) so he will make sure that they make it right if I choose to revisit the issue. So glad I went with this company. Love the owner. He's great to work with.