What us middle aged climbers are really interested in is people who have maintained or improved their grade at at an advanced age. That, e.g., Moon can manage 8b+ or whatever it is at the ripe old age of 48 or so is of course impressive, but not so astonishing given what he did when he was 40 and what he did in his 30s. Is Haston unusual, even unique, in managing to improve in his 40s and up until the age of 50 (in terms of sports grades at least)? I'm thinking of people who climbed to a decent standard beforehand of course - it would be easy to improve if one bumbled around in one's 20s and 30s.
Then, the crucial question, can I improve without having to shed 10kg? That's basically what Stevie did at crucial moments as far as I can tell from his blog. And that Bleausard climbing Zen at 70 in the guide (I think I've remembered that right) - well, he looks like a bag of skin and bones (plus a bit of muscle).