Yeah, people underestimate how much GVT affects your nervous system...even during the workout, its more nervous system failure than muscular failure (but that's supposedly how works so well for hypertrophy). From what I've read, 6-8 weeks is about as long as anyone's body can take it
When I was doing heavy duty, I'd do 2 sets to failure per exercise. 1 very heavy one and one slightly lighter for higher reps (but still maximum of 10) and both to failure...and I'd only train 3 (max 4) days per week...hitting the whole body every 8 or 9 days or so...Looking back, I should have done things differently..when you're 21-25 your body can take the 500-600 squats and deads for reps month in and out but I couldn't do that now...nor would I want to.
I'm starting back tomorrow after 2 weeks off as I've been in hospital over Xmas and had a small surgery about a week ago. I got wounded quite badly and I've lost count of the number of operations I've had on my right leg...sucks...especially since I'd forgotten I even had to go in for it lol....still, got some morphine pills. 100mg but don't want to take them as I've had problems with painkillers in the past and I'll get dependent again really quickly if I do .