This is the first Iv'e heard of it.
The easiest way to find out if it's true would be to test it out I suppose.
Edit: Did some searches and didn't find anything. Where did you hear about it?
On the USEP wiki. I think the combat section under spellsword.
I'm pretty sure it would work. The Bound Spells all level up Conjuration and their associated weapon type so all the perks should apply, but I asked because I've never used Dual Flurry until this character and haven't used Conjuration spells.
Yes, I know they do work on the Bound Sword spells.
I'll test it out myself, I had just wondered if it was someone blowing smoke up my ass or if anyone had actually tested this. I'm fairly certain it said that Dual Flurry worked, but not so sure on Savagery.