Deda Velocita clamp area damage, common?

I have 40cm c-c 31.8mm chromo deda bars, fit to an Easton Vice stem, used a torque wrench and kept below the max recommented limit by 1-2 units, took the bars out of the stem today(used by me for a couple of weeks, both bought new)and theres a huge indent/impression left from the rear of the clamp, nothing from the inner face plate.
I use carbon assembly paste too so that I can use a little lower torque in the bolts, the paste is good for metals, not just CF.
I saw marks on another set of these I was supposed to buy second hand, so didnt buy them. Whats the deal, thought being heavy steel they would take more torque than allu bars(and I played it safe), should I bother trying for a return refund from Ribble or will they say its only under warranty when paired with a Deda stem?

bump

just found this from may 2011

"Just took the bars off my bike and found that some numpty has over tightened the stem which has caused a little denting. "
http://www.lfgss.com/thread66255.html

I think you will be hard pushed to get a refund, they will simply say "you over tightened it" or "buy these bars". Check your torque wrench, make sure its not faulty.
I have heard steel bars dent more easily than Alu, I suggest you just tighten it up by hand.