"Modern man is obviously weaker than his ancestors... there again we do sit on our backsides all day, have cranes and forklifts to pick up anything heavy, and have health and safety limits on how much you are allowed to pick up, even if you have a manual labour type of job... and then stick it in the boot of the car, rather than carry it home. You would have to be fit/strong, there is very little in the way of automated/mechanical help, so no reason why a well fed healthy man could not pull these weights. 220 yards is a LONG way, I have yet to attain this with a 'modern' longbow, as I am just up to 85lbs now, but like everything else you train up to it..."
Which means that modern man is not actually weaker than in the 'olden dayes' but simply that fewer need to use or develop their muscles.
"I am fairly sure there is a raising of bow weights as time passes, stopping around the WOTR. Why would I need a bow of 200lbs just to kill an unprotected horse or someone wearing chainmail? As the armour vs weapons race goes on, bow/armour goes up, same as guns and armour does now."
Where is the primary source material for draw weights? Draw weights are not the only indicator of performance, it can be misleading simply raising a notional draw weight.
"I quite like Pip Bickerstaffe's idea of reverse engineering from the size of the nocks in the MR shafts...the gap would dictate a bow of 100lbs or so. "
You might also consider the amount of strings to bows bought, my suspicion is that the strings were changed with great frequency, if you look at the knock widths the strings cannot have been too thick, has anyone done sample tests with the higher poundage bows?
"So re-enactors should really carry and use bows of at least this size, otherwise they are cheating. In my book that's like wearing modern shoes... ""
Either carry a bow that looks like it pulls heavier - fine.
Or
They are simply carrying lighter bows for game
