I do it all the time as well. Good thing about potting mix, is that the plants zap a good chunk of the nutrients out of it quickly when in the pots (bags). Since you didn't use crap ferts like say, Miracle-Gro, salt buildups should be minimal. That said, overdosing on NPK isn't likely. Keep in mind that it will break down rather quickly due to all the organic matter - come Spring, it may be near where you are now and look like you did nothing due to compaction and microorganisms breaking it down. If you keep after it, the low spots will fill in nicely in time and you have the benefit of great recycled soil! If you run out of low spots, spread the remainder in a thin even layer over your lawn about a 1/4-1/2 inch thick in thin areas - will give a nice organic boost!

Damping off is a seed disease which prevents germination and root establishment. Once a seed germinates and the plant forms, then damping off is not an issue. I can't remember the last time damping off was mentioned on a lawn forum. The standing water is the problem. Now the question is how to make that standing water drain away. Are those holes or otherwise low spots in the yard?

What do you mean by this? I mean I can't tell what is going on with the soil. A CEC of 11 in most cases would be indicative of a silty sand soil (although very very weathered clays can have low (5ish) CEC, so maybe your soil is a very weathered clay and the rest of the CEC is due to HM%? A W.V. of 0.82 is really unusual- indicative of a soil with a lot of OM. Even pure clay soils are above 1.0. If your soil isn't weathered clay, it must be a sandy bog? lol J.K. A HM% (a measurement of very stable OM- SOM) of .24% is not high by any means--so probably not much OM in your soil. So CEC must not be coming from SOM. What kind of soil has a W.V. less than clay and very little SOM content? I just can't contemplate that you added that much peat and Kow, but maybe you did. Anything is possible, it's just that your soil (or at least the data reported) is unusual.

For those of you who are unfamiliar, Neil Sperry is a Texas based garden guru. He has a radio show and is syndicated in many of the big news papers in Texas. Neil Sperry is the bane of my existence. Whatever he says, I do the opposite. I followed him from about 1992 to 2002 and realized my grass looked worse every year. Then I switched to organic and learned a lot about lawn care on this and other forums. He, apparently gets all his information from sponsors selling products. I could make a living following him around to fix the mistakes he has people making. Sunlight - Neil says, St. Augustine needs 4 hours of sunlight daily just to survive, and 6 hours of hot, direct sunlight if you hope for it to grow vigorously. Again, my front lawn in SA had zero hours of sunlight per day for the duration of 25 years. It was under the canopy of several very large live oak trees. For 10 years it deteriorated, and for 15 years under organic fertilizer, it looked great. Here is a picture of my grass grown in the most dense shade in that yard. Looking straight down reveals all the flaws in the turf. What you can see is the grass was growing outward and not upright. When it is in full sun, it grows more upright driven that way by the sheer amount of grass. Here is the same yard from an angle. The house faced north and this is the front yard. There is a huge tree to the left of the walkway and two large trees in the bed to the right. This yard got no direct sunlight at all. You can see grass invading between the bricks and over the concrete. It is not doing poorly. Neil Sperry would say this is impossible. Here is a picture of my current house - back yard, south facing slope in full sun. The grass is dense. You can see the grass needed fertilizer, but besides that...in the foreground is weeds mowed at the mower's lowest setting. You can see the St Augustine runners expanding their territory into the weeds at a rate of about 15 feet per year. You can see the hose and a long handled yard tool sort of buried in the grass. The only reason you can see them is the grass is too dense for the hose and tool to sink farther down. You can tell the depth of the grass on my dog's legs. They are buried to the hock. Drought - Neil says, St. Augustine needs more water than most of our other lawngrasses (fescue excepted). If you let it get too dry, and especially if you do so repeatedly, St. Augustine will be weak, and it may even die away. This is about the worst thing you can say about St Augustine. The main reason is it is bordering on untrue. It "may" die away. St Augustine is not bermuda. Bermuda will come back from no water for a year. Here in Bandera I had a side yard where the St Aug was golden brown. It had been that way for months before I bought the house. I figured it was dead and neglected it for another year, which was a drought year. But when I watered it, the golden runners came to life. It was solid St Augustine. Had this grass been in full sun, it "may" have died away, but for whatever reasons, it came back after getting no irrigation from June to March. Here is a picture from my previous house in George West, TX. The grass is 32 inches high and had not been watered for many months. You can see the top of my dog's tail and her ears (different dog). When you mow St Augustine high, it needs less water. If you don't mow it at all, it needs no water to thrive. Please do not let the so called drought intolerance deter you from St Augustine. Fertilizer - Neil says, in part, ... Most clay soils have excessive amounts of phosphorus (middle number of the analysis), so soil tests usually suggest a high-quality, all-nitrogen fertilizer be added. What the hell? Who has clay in Texas??? Okay, now the OP describes his location as between San Antonio and Del Rio. As it turns out, there is a pocket of clay soil in D'Hanis, TX, along that route, so this might actually pertain, TO HIM, but almost noplace else. Clay soil is a red herring. Get the soil tested if you absolutely cannot grow anything. Otherwise, go with organic fertilizer and see the miracle unfold. Disease - Neil says, Gray leaf spot is a fungal disease that shows up in mid-summer into early fall. You’ll see diamond-shaped, gray-brown lesions on the midribs of the blades and occasionally on the runners themselves. This disease is most prevalent following applications of nitrogen. In fact, the additional symptoms of gray leaf spot are yellowed leaves that look like they need more nitrogen. I get gray leaf spot any time of year. My lawn woke up with it this year in early spring. Caused by too much nitrogen? I get it after months and months of no nitrogen at all. Like now, for instance. The lawns on his St Augustine Diagnostics page are all mowed way too short. Between that and his comments on drought scaring people into watering too much, it's no wonder people have problems with St Aug.