Yes. When you apply a pre-M it is essentially creating a soil barrier where any seed is either already coated or will come in contact with soil that has been coated (say if blown in from a neighbor's yard). Think of it like a blanket. Now when you go and pop holes in that blanket you potentially expose new weed seeds that were dormant under the soil (and not in contact with the pre-M), and more importantly you now leave pockets in the lawn that weed seeds could enter from the air. Basically you're partially negating the purpose of the pre-M. I think not doing a pre-M would be a very bad idea. Thin areas WITH poa already present (ie producing seed shortly or already) are just asking to be completely taken over. Remember that compost IS a fertilizer (in a sense). While not a large dose of nitrogen like a chemical fertilizer, it does provide benefits to the soil through the biological organisms it houses (break down of thatch if present, better environment for the grass by reducing moisture loss, etc.). So no I would not fertilize until 5/12 to attempt to reduce the propagation of poa. But we're seriously talking 2 weeks here. Split the difference and do it next week (5th)! As mentioned before seed is not for you so the idea of planting plugs (sprigs) is exactly what you should do, after you aerate the compacted areas, plant the plugs (look up the proper way to prep the ground for plugs), and then apply a thin layer of compost. Then keep those newly planted areas from drying out.

Since you are watering so much you lose a lot of the fertilizer nutrients due to leaching. Also new roots are extremely short, so a lot of the nutrients are unavailable once they move down a few millimeters into the soil. What I like to do is apply a half rate at seeding, and the other half after the second mowing.

>>seeds will not germinate if any type of weed control has been added. Well, not reliably, and even if they do, some gets taken out by the herbicide. One thing you can try is a soil flush--water a lot more than you normally would to drive the herbicide down into the soil profile. Don't allow runoff or extreme puddling, but small puddles that are temporary are fine. Fortunately, complete failure from an herbicide is rare (although there are a few I can think of that would cause almost complete failure), but it's definitely going to have an impact on how much seed sprouts.

Before I reply to your post, I'll reply to some of David's comments. "There is only one organic fertilizer that will burn that I am aware of. That is blood meal applied too heavily." Uncomposted poultry manure can also burn. I had access to uncomposted poultry manure many years ago and saw it burn when it was over applied. "No matter what you can't trust the settings on a spreader to apply the correct amount of anything organic. Some settings are close, but with organic, no settings are even close. You will have to calibrate your fertilizer to your spreader. Not to chastise you but if you know how much land you have to cover and how much the bag covers, most people will realize when they finish one bag and have only covered 1/4 of the expected area, that something is wrong." If I read the original post correctly, he had covered 1/4 of the area with 1/2 of the fertilizer. He realized something was wrong and posted here before making it worse. IMHO, it doesn't matter whether you use chemical or organic fertilizers. Either way, you shouldn't use the spreader settings to determine the application. There are too many variables. I always calculate how much fertilizer (or seed) I need and adjust the spreader settings based on how much lawn I'm covering versus how much I should be covering. I also try to make multiple passes at half the rate so that if I misjudge, every spot gets some, but some spots get more. I'm assuming this is the fertilizer you applied. I'm also assuming that you didn't really apply 2.5 tons of it on your lawn. The biggest bag they carry is a 50 lb bag, so I'm going to assume that's the one you used. I could be wrong, but I think that since they have 7% water soluble nitrogen, even 50 lbs could cause burning in your situation. You said the front lawn is slightly smaller than the back, and you have 10k sq ft total and you ran out after fertilizing half the front lawn. Since you say "a bit" smaller, I'll assume the front is 5000 sq ft, so you applied the bag to 2500 sq ft. If the bag was a 50 lb bag, you applied about 1.4 lbs of water soluble N per 1k sq ft. That's high, and may cause burning, but it may not be high enough to burn. If the front lawn is significantly less than 5k sq ft, you will be more likely to have burning. If you didn't mistype in the original post, and you really applied 5,000 lbs of this fertilizer to 2500 sq ft, I don't think anything will grow there for at least a year.