lifts don't always go down, but they do stall, it is really hard to not overtrain as well, and you are always fighting some lame injury, I learned the importance of active rest/recovery though and was able to actually keep most of my strength last year. It usually comes back within 2 months if you lose some, as long as it wasn't due to an injury.
as far as a split goes do you mean now, or more what i would do in-season?