I asked this on newbie and nobody answered, maybe some imm can help, please?

Does berserking, so reducing your skill at it, help learn weapons, or make it worse? If I am at 85 with axe and berserk so I'm effectively 75, and I'm using a practice weapon, will I learn it more easily or less easily or no affect?

Berserk never hinders your learning.
Berserk makes you fail skills more often.
So only skills you can "learn from your mistakes" are aided a bit by berserk (because you make more mistakes, so you can "learn from your mistakes" more often).

You learn one of 2 ways as I understand. You can learn when you succeed(1%) or when you fail(1-3%).

So if berserk drops your base percent from say 75% to 65% your chance for a fail/learn(1-3%) goes up but your successful learn(1%) goes down.

Does this just not apply to basic weapon skills or all skills?

Pretty sure for things like weapons, each time you swing your weapon you have a chance to improve. There isn't a "fail" (being dodged, parried etc. doesn't count as a fail).

However having skills like second, third and fourth attack perfected will make you swing more often in general, so you would learn a weapon skill faster that way...so if you have one of those and it isn't perfected, you could make a case for saying berserk is hurting your learning rate of a weapon. But so minimally I wouldn't even really be concerned about it.

It drops your skills as well, does it drop your learning rates?

For skills that require you to be successful to learn, such as riposte and concealed, having that lower percentage hurts you.

For active skills and other skills that can improve on failure, it depends on whether the learning rate is calculated on skill attempts or if successful and failed attempts have different rates.

My anecdotal experience tells me that most skills fall into the "skill attempts" approach where success and failure are treated the same. In that world, the chance to learn 2%, 3%, or even 4% represents a huge savings in time spent training.

Is it some gnome perk?

High wisdom or Apt Learner.

Ok, so where do you think learning weapons falls?

And any imm care to clarify/confirm, please?

berserk is not a good thing for weapons training.

I don't think you ever learn "from your mistakes" on weapons do you?

I do know for certain you CANNOT learn from a "miss." I know this from doing a super high AC + low hit roll build that could perma tank kobolds and never hit them. No skill gains on weapons.