Well i just came across this topic and i wanted to give my input.
About a month ago i decided 1.75x dura loss is completely ludicrous and cannot possibly be correct. I did some googling and most people either never noticed a difference or blindly followed what the wiki said, while others stated that you can't always trust the wiki. I set out to test it for myself; and though I did not go nearly as far as NomadTrooper to document my testing, I can say it came out the same.
I actually used a single ice wand; but i tested it again with a different wand. Again, this was a while ago so i can't remember the exact numbers but it came up to around 170 bolts without meditation and 160 bolts with meditation. I honestly don't know why it was a bit off the second time, but it came out nearly identical with the second wand i used.
The point is, since then i've been using meditation non stop and have not noticed any particular spike in dura loss. As long as you preserve your wand and don't smack things around with it, it shouldn't be losing much dura in the first place. I wasn't too certain if what i came up with was correct but now that I see someone else has tested it I think it's safe to say that meditation does NOT negatively affect dura loss; at least not in any substantial way. Maybe it increases dura loss when you use melee or something. I frankly don't know xD