Shot in the dark here but what specific things are people reviewing in PT4? There are easy things that are indicators like an increase in vpip and running +/- ev but I am looking for comprehensive stats that would be useful in identifying a leak.
There are various reports for BB/100 that include:

-by HU only stats
-by position
-by # of players per flop
-by 3/4/5 bets pots

None of these specific stats listed are showing me much as far as obvious areas of concern. It is challenging however, to know what the numbers actually indicate though. If you don't know what specific results fall in the accepted range of proper play, then its study without purpose. For example, if your results all still have positive ev no matter how you break them down then that isn't helpful. For instance, if you know you play out of position too much but are still profitable from every position then how do you proceed? That leak has to be identified and addressed. You could certainly play sub optimally at 2/5 and below and still be profitable but you would absolutely get wrecked if you moved up.
I guess I would like to not rely on intuition for improving my game. I would rather look at data to identify leaks, but in order to do that you need some reference points, thresholds, and acceptable ranges to make it all make sense.

After all that rambling my real question is what stats ppl are looking at and what number has to be present for that stat to be classified as a leak? We know if your VPIP is 60% at 6max you're not playing disciplined enough.