Actually I would not think that too many people have reached their full potentional, strength wise, no matter how many years of training they have undergone. . Nature always seems to hold something in reserve as far as strength is concerned. Once or twice a years there's always that story about the little old 105lb lady who rushes in and lifts the rear end of a pick-up truck off a child trapped underneath. I don't think that that little old lady worked out heavy on partial power rack DL's for set's of 3's with 1500lbs + on a bi weekly bases. That same little old lady may have been sore all over her body for a week or so, but the usually case is that she may never really suffer any major, long lasting injury(s). Once back to her Bingo game, she's as good as new. In other words, no one really knows their full strength capacity under stress.
When lifting progress seems to stagger and stop after so many years of lifting (I'm talking 10-20 years plus) than maybe the training methods and recovery time should be looked into. Unless there is nervous system disease, serious joint and back/spine problems, etc, progress still should be obtained, however slow, but increase it should. The advancing age can have a important bearing on this of course. But I've been to quited a few PL'ing meets where some of the men are in their mid fifty's or even the 60's and still are meeting or going beyond their personal best. It appears that there are more senior lifter now than ever before. Lifting for life, indeed. If a 35 year old experienced and healthy lifter hit's a stone wall in training than it might be time for a whole new restucting of his training program, including diet. There would be doubts that he had reached his full potentional at that young age. But in most cases, the mental outlook will be the key factor with regards to training progress, at any age of training.
As far a pure muscle size goes, Coleman, Cutler and some of the other massive Pro's seem very close to that edge of meeting their full potentional. Though I may be totally wrong and the next ten years may produce men with a cut to the bone 30" arm. To get the complete impact of their muscle development one would have to see them in person to really understand that awesome muscle mass. Pictures or videos don't come close.
TexR may have to go in another direction and overhaul his complete training methods if he's stuck with slow and stop training results. Might want to take a couple of weeks away from training of any kind. If he loses a lot of muscle size, in that two weeks, than he wasn't training right in the first place. Hint: Less is always more with regard to serious training. Also another little gem: Going to failure in every workout can be selfdefeating. Good Luck.
