I know that historical sources and modern practitioners offer a lot more information about swords than about "impact weapons" like axes and maces. But maybe there's nowhere better than this forum to bring up a point of curiosity about those latter weapons.
For discussion, let me clumsily refer to two categories of these: sharp clubs (axes, picks, maces with sharpened flanges or spikes, etc.) and blunt clubs (blunt maces, hammers, etc.).
I know that both types can strike devastating blows, with more than enough wallop to take down even an armored opponent. No argument there. But as deadly as a blunt club can be, it would seem that a sharp club of the same proportions (mass, length, etc.) would be even more effective against a foe. Better able to pierce armor (a pick's spike), or better able to cut deeply (an axe's blade). (After all, if sharp clubs didn't offer these advantages, I don't see why people would have bothered with the work and cost of making them...)
Yet it seems that maces saw a fair degree of use among knights and soldiers. So, I wonder: Are there any ways in which a blunt club is actually better than a sharp club on the battlefield?
Here are some ideas and guesses. Do any of these make historical or practical sense?
1) Cost: I assume that a blunt club, all else equal, is cheaper and easier to make than the same club with an edge or point. (This alone, it seems to me, could perfectly explain historical use of maces over axes and picks, especially when lots of men need to be equipped.)
2) Ease of care: An edge will chip and dull, and a point may bend, but a blunt club seems as trouble-free as a weapon can get...
3) Ease of use: Perhaps a blunt club is easier to use, in that there's no need to properly align an edge or point to maximize effectiveness. (I have no idea whether this is actually a point of difficulty with axes and picks. Any practitioners with insight into this?)
4) Handiness outside of combat: A soldier's camp always needs hammers! (Then again, that's also true for axes, so this may not mean anything...)
5) No sticking: I've always heard that picks (and maybe axes too?) can get "stuck" in a foe, while a blunt club would normally never face this problem. (Did axe and pick users really have to deal with forcibly wresting their weapons out of enemies' armor or bodies? Do historical sources mention this?)
6) Less overkill: Perhaps blunt clubs were just as effective as sharp clubs at taking foes out of a fight, without killing them quite as often. That would leave more downed foes alive for interrogation or ransoming. (I don't mean to downplay the deadliness of a mace, but I imagine the weapon would leave fewer foes dying from severed arteries... Any backing for this?)
7) Ideal vs armor: Perhaps blunt clubs were actually better than sharp clubs at hurting a foe encased in steel armor. (I don't see why that would be, if the weapons were equal in length, mass, etc., but maybe there's a reason?)
8) Batter up: By not diverting energy to penetration of armor and flesh, it seems blunt clubs would impart more momentum to foes, possibly knocking them around more easily. (Again, I assume that sharp clubs deal more harm to flesh – otherwise, why invent them? – but knocking foes down is still a mighty useful effect.)
9) The old je ne sais quoi: Perhaps there were cultural, social, symbolic, or other reasons why a knight might select a mace when an axe or pick would actually be more potent on the battlefield. (Any merit to this?)
Looking at that list, I definitely see 1) cost, 2) ease of care, and maybe 3) ease of use as likely reasons for selection of blunt clubs over sharp counterparts. The rest, I'm less sure about – do any of those, or something else entirely, represent actual advantages of a blunt club over a sharp one? Or is the answer simply that knights and soldiers typically didn't choose blunt clubs over sharp clubs if the latter were available?
I don't know. Does anyone have information or insights?

