PS4

http://www.uesp.net/wiki/Skyrim:Combat#One-handed_Combat

The wiki mentions that One Handed ranks and (armsman) perks stack with smithing. But it doesn't mention potions.

For example if I have 5 ranks of the armsman perk (+100%) and I drink a potion of Fortify One Handed the display on the potion says +50% One Handed (and not +XX skill ranks) is there some cap or diminishing returns? Or is it all 'stacking'?

If you have any ranks in armsman why don't you just go drink a potion and see? if it goes up by exactly 50% it stacks, if it's a smaller number it doesn't. It's not like you're in my shoes. I got mods that change stuff like that. You can't on PS4 so you're actually an ideal candidate to test it.

Sounds good. Will I see the damage on the tooltip when I look at the weapon? Or do I need to test how fast some enemy dies?

edit: and by the way I don't have any armsman perks specced. I do have maxed alchemy (completely perked) and I can make pretty strong potions of enhance One Handed. But I have some skills at 100 so I could use a save game point and make those perked 100 skills legendary and then test this stuff out. I could put the recovered perks (from unrelated skill to legendary) into the armsman and test stuff out. It would be a lot easier if I know that the tooltip number is reliable. Or know that it is not reliable and know I need to test it on an opponent.

I don't have the almsman perks and I asked the question because I wondered if I should put some in armsman but was curious about the interaction with potions as my build likes alchemy. So I asked the question to help plan out what to perk as I continue the game.

alright, the damage shown on the tooltip is reliable to a degree. it wont show fractions but it's good enough. if you have a potion with a nice round number like 50% it might be easier to use that. Just take the perk and then the potion and if you have 50% more damage after the potion than you did before with just the perk then it stacks.