I started noticing that whenever I use this staff it doesn't seem to want to work anymore. It's fully charged up with soul gems so that is not the problem there. I am on 99 conjuration, could this be the problem?

Its the elemental potency perk.

Enchanted items have no underlying skill requirement (other than Enchanting and that has more to do with Charge used per cast). So, your Conjuration skill would have no effect on this item.

Actually the higher his conjuration skill the less charges a summoning based staff would use per use. Don't know if that applies to the Rose though.
In any event as I said the elemental potency perk interferes with summoning staves.

There is a bug listed in wiki that if you have the conjuration perk called elemental potency, the sanguine rose will no longer work.

http://www.uesp.net/wiki/Skyrim:Sanguine_Rose

Also, make sure you're trying to summon in a valid location - the crosshairs turn red if you're pointing at a spot where the summons won't spawn.

Took me a while to notice that one.

Yeah I figured out this didn't want to work when I was fighting the Caller, needless to say some shopkeeper is very happy now.

I still never really understood what happened on that quest.

is this the same for all magic or just Summoning? Because that is not how it is supposed to work.

Sanguine made you have fun.

heh. its one of my favourites because its so random.

Maybe you can give it to your follower...your perks shouldn't interfere with it if it's being used by your NPC.

Um... yea. But how?

...nevermind, maybe I shouldn`t know.

He made you have a drinking game incognito. There could have been a bit more fun but he did his job as the god of debauchery and so forth.

AFAIK, it's for everything. Having a good Destruction skill will make your enchanted elemental damage weapons/staves last longer on a given amount of power as they use less charge per strike/use and so on. Perhaps having something to do with how the keyword system works with perks like the Illusion terror perk and Flames synergy and the newly discovered Necromage/Vampire synergy.

Needs some fixing if it's a bug or at least some tweaking if it's a design decision as it's very wonky behavior that seems like it shouldn't work that way at all as you state. At the very least it'll be something that is altered in a modded bugfix of some sort I'm sure.

Actually that's exactly how it's supposed to work...one of the loading screen hints even says so.