If someone like meso claims some pretty impressive lifts as a natural trainer, I don't call BS automatically. I've been in the gym on/off for the past 23 years, and I've seen first-hand some pretty freaky lifts from guys that you wouldn't expect based on their size.
Myself, I'm a lifetime natural trainer. At 5' 10.5" and currently around 295 lbs with about 18% bodyfat, my lifts are not that impressive based on my stats on paper. In fact, I don't look like a 295 pounder in my opinion. I think I appear to be 265 or so. My best lifts are only 135 lbs decline DB presses for 8 reps, 140 lbs DB incline presses for 7 reps, and 110 lbs DB shoulder presses for 8 reps. Again, not very impressive based on my on-paper stats, but I'm happy with them so far as I keep my form pretty good on them (I try to mimic Dorian's exercise form and rep speed; I think they work best for me and keep me relatively injury free). I can look my kids in their eyes and tell them that I have never ever taken drugs (for bodybuilding or recreational) if they ever ask me, which I am proud of.
Meso states that in 3 years he increased his reps on a particular exercise using the same weight from 3 reps to about 6 or 7. This sounds about right. Why automatically BS? Maybe he's telling the truth, and that his genetics are just that good.