Could do that. Though, personally, that feels like more of a cheat.
That being said it doesn't seem to be that great. Played around with it in the arena and nothing spectacular happened, if it was substantially better than an iron warhammer I didn't notice.
Is there any possibility that it was because this test was done in the arena? There are a few things that just don't work the same in arena as in fort or adventure modes.
Also, was your test with an artifact slade warhammer? If nothing else, I would expect the extra bonus from being an artifact to help it be noticeably more dangerous than a plain iron warhammer.
Pretty unlikely. Nothing about the arena should impact the way weapons work.
Artifact status applies a to-hit modifier and a masterwork level sharpness modifier. The problem wasn't that it was missing it was that when it hit a steel breastplate over steel mail it bounced right off. It caved in skulls and snapped necks pretty good, about as well as an iron war hammer.Even assuming that an artifact slade warhammer was much better than a plain iron warhammer that would logically just elevate it to the level of an artifact iron warhammer.
In large battle tests with 15 steel clad dwarves with warhammers against 15 unarmed steelclad elves team iron actually did substantially better than the guys with slade. Team Iron succeeded in bashing their enemies helmets until they stopped having helmets, Team Slade had to pull off the helmets to finish the job. When Team Slade had no points in any combat skills they repeatedly lost (to unarmed elves) because they were getting tired lugging around full kit and 80 urist hammers. With untrained fighters adamantine warhammers are actually better than slade.
When I took the steel armor off everybody untrained guys with slade warhammers did okay but they still tended to lose people. Grandmaster everything hammerdwarves with slade warhammers cleaned up unarmored elves but they still took longer than the guys with iron warhammers and only did a little bit better than grandmaster everything unarmed dwarves.
Slade Warhammers seem to be at their most dangerous when you convince your enemy to hold them.