The stewards have a set of percentages that are used to determine the type of penalties that are dished out for exceeding track limits without clear indication of there being no advantage gained, or attempting to negate any advantage. Obviously, if track limits are exceeded once or twice in a race and there has been no advantage gained, you're not under threat of receiving a penalty. If you are consistently exceeding the limits though, even if it is once every few laps, you're likely to get noticed and potentially taken to the stewards, where you are reviewed as to how many times you exceeded those limits and whether there was a clear attempt to negate any advantage.
Now what I mean by a clear attempt is fully off throttle, for maybe half a second to a second, or more depending on how far you went out and the potential amount of time you could have gained. This should be done on a straight, away from braking zones and corners. The clearer the attempt to negate an advantage, the easier it is for a steward to spot, and not count that excursion. Certainly don't do it by taking a corner 5mph slower than normal, or lifting into a braking zone, or coming partially off throttle but still being on it. I would say staying off the throttle (completely) on the exit of a corner would be suitable if it is long and clear enough, and would be allowed. Any times you exceed limits and it is clear that an advantage was not gained, either by clearly losing time or by clearly lifting, that moment will not be counted.
The track limits are simple, it's the white lines at the edges of the track, and do not include the curbs. You must have two wheels within these white lines, or at the very least on them, at all times to be within track limits. Don't use the games limits, unless those limits are tighter/stricter than ours for a corner. Unfortunately spa is quite bad for track limits as curbs are big, and there is usually astroturf on the outside of them before reaching grass or gravel, but it doesn't mean you can use those areas. Generally, if you hear both sides of the car touching the curbs, you are very much on or over the limit. If you are ever in doubt, drive a lap in practice, and watch back the replay with trackside and chase cam to see if your lines are within the limts. If they're not, you will need to adjust them so they are within limits.
As for running wide on corners, that is still gaining an advantage. Unless of course it is clear that it was a mistake and you lose time. Going wide on the exit of turns often means you have gotten on the throttle earlier, or taken more speed through and out of the corner than you would if you were driving to stay within the limits. Going wide through blanchimont or eau rouge and keeping your foot in is quicker than lifting to stay within the limits. You are gaining time.
If I were ever going to put a number on the amount of times you can run wide on a corner, or cut it slightly, or just exceeding track limits, it will be 0! That is the number you should aim for over the course of the race, and if you do lift each time that you run wide, as painful as lifting it may be, that number will be 0. This rule isn't there to penalise the faster drivers for being fast! It is there in the aim of fairness for everyone across the league! Everyone has the same track limits. Everyone can easily stay within the track limits, and still be fast. The fairer the racing is for everyone, the better and more enjoyable competing in the league is.
I'd like to ask that the continuation of the discussion is kept civil and subjective, with no name calling and avoiding pointing fingers at members or staff. If you have any questions, of course feel free to post them for people to discuss and get answers on for all drivers in the league to see so everyone is on the same page. If you do wish to discuss something privately, please don't hesitate to contact me or any of the other Project CARS league coordinators as we'd be more than happy to help. We're here for you guys, to help and to make the league as fair and enjoyable for everyone as it can be. Track limits are always a heavily discussed topic with a mixed bag of opinions. Be mindful and respectful, as it would be a shame to see things turn sour between people this early in the season.