IIRC in simple terms work x distance = power and one can get a general idea of energy stored in the bow with: draw weight x draw length /2. Of course one would have to lower the result a bit (maybe 5-6% for bows and 10-20% for crossbows) as the power stroke is shorter(the actual distance the string is pulled back)

Stuff like that just makes it all even more complicated as we cant just compare draw weight but have to know the actual draw length. Even for bows there would be a difference as a tall archer might have longer arms so "drawing to the ear" would be different than for a shorter archer.
Indeed, also a longer Draw might need longer arrows, (possible if unlikliy), which would only increase the problems.
I don't like the idea of comparing crossbow strength with bow strength, they are too different in technology. The bolt is short and is set in a guide and though the 'draw' may be short, it usually requires a machine to draw the string which itself is like a rope compared with a bowstring.
The bows of the time were nothing like todays takedown recurves or compounds, they did not have a riser allowing 'centre shot'. The archer had to find a way to overcome the archers paradox. When loosing an arrow, its natural path would be central, in line with the string, however this is not possible. The Mediterranean 3 finger draw requires the arrow rests on the back of the bow hand and the paradox is the means by which the arrow contorts its way around the bow. This requires an arrow of correct spine be used otherwise it will not fly well and/or will not be accurate. The correct spine weight will also be determined by the length of the arrow.

For example, using modern shafts.
40lb spine at 32" length. Cut that down to 28" and the spine has effectively been increased to 48lb. Likewise a bow with draw weight of 40lb at 28" is lighter or heavier depending on draw length, it equates to approximately 2lbs per inch.
Of course, the cast of the arrow will be greatly affected by the weight of the arrowhead and the size of fletchings. Even then there may be some slight adjustment that will perfect the cast.
My own draw length is roughly 28" and my bow is 45lbs. After years of experimenting, I get best performance from 29" arrows, 5/16" diameter, 100 grain piles (points), 5 1/2" low profile fletchings (5" normal fly just as well but not in cross winds) and the spine is 40lbs.
By using a lighter pile of say, 63 grains, the arrow becomes stiffer and will fly left.
It goes without saying that the correct nocking point on the bowstring has to be located to prevent 'porpoising' of the arrow.

Given the heavy weight of the old Warbows and the bodkin heads and the fact that these archers drew to their shoulder, the arrows can almost be mistaken for broom handles

.........Orda