Enhancement Tiers for Weapons?

I understand where you're coming from, but there are exceptions.

Actually wouldn't that exception more than likely be the rule. I mean we have tiers that are set-up in 50 attack intervals with hammering adding (typically) up to 10 attack. From a numbers standpoint you're more likely to not need to hammer first the majority of the time.

Of course we need to factor in starting base attacks. I think we are at a point where a lot of weapons do come in that sweet spot of 105-114 wattk clean (or 5 lower for weapons with 8 slots).

Edit: That's also assuming a small amount of enhancements, the more you add the more likely you get into a higher tier but if we are talking about mass enhances they are typically guarded anyway so preventing a loss of hammers is moot.