Really, Leon? I'm sure I would be careful using the poll of an axe to knock in a few nails, but I'd weigh the possible risk and take into account that the tool wasn't really designed for the task I was putting it to. But how about something like the Estwing Universal Hatchet? That has a purpose designed hammer poll. It's probably not as balanced as a proper hammer for hammering in nails, but it would get the job done and it's got to be better than a knife pommel.
It's just a personal preference mate, I like the estwing and have cleaned up one that has been used for hammering things in, it was a swine to sort out and as a result I wouldn't want to do it to any tool I owned. I do also recall being told not to strike an axe with anything metal and as a result wouldn't want to strike anything metal with an axe.
Don't get me wrong, I have no problem with versatility. But crucial to the whole business of kit selection for survival/bushcraft/wilderness living, etc. is knowing where the sensible limits of a particular piece of equipment lie. That way, you end up with knives that function decently as knives and not with unwieldy and costly monstrosities like the WS Dartmoor knife that try too hard and don't do anything particularly well.
The SBT I've seen and handled (but not used) looks a really nice knife. I'd love to own one, but I can promise you that, if I did, I'd never use it for hammering in nails
Burnt Ash
I agree with you mate, versatility is a big thing and required of many tools, but in my case trying to drive in nails with the poll of my axe would be hazardous. My axe is the GB hunters with the flay poll, it's rounded and quite highly polished.
As you say it's knowing the limits of the tool in use. My opinion may differ once I get a chance to play with the Norlund axe, but I have never really liked the idea of pulling back a sharp edge in the direction of my head whether it has a mask on or not. It's the same as the knife butt being used as a hammer, a distraction or not paying full attention or even being tired could have nasty results.
In the end it's also knowing your own limits as well as those of the tool in use I suppose.