Here is what I do. I cut some of the thickest stuff off but leave a good 1/2" or fat on it all the way around. I usually get about 1.5lbs of fat off when I trim. If you went down below 1/4" or fat that could be causing some of the issue with the moisture level.
I started with not trimming at all and learned what I liked and developed my trimming habits. Have you looked at the video of Aaron Franklin doing his brisket prep? If not its a good watch
I hope this helps.
Very easy to suffer from a case of OCD while trimming anything. I mentioned to the wife we will probably be having brisket again for New Years. We may be having it bi-weekly until I figure this out. I very well may try just knocking the hard stuff off on one.
Just got "the look" from the Boss....she has an appointment at 9:15, gotta go.