Squats

Pakewi,
I found in the past that I forgot to look at myself as a human and would trudge through weight workouts of a few sets of 3-5 reps using a 7 rep max, in other words I would not push myself to extremes. If the required stimulus is not there then there will be no adaptation as you have mentioned.
I still adhere to Charlies principles with regards to high/low days (I actually have no low days, just three sessions a week, all max intensity), however I am not as conservative as Charlie was and usually train till my eyes bleed!