Roy, on my scale "not infrequently" is less than "usually" and a bit less than "frequently". Sort of means that they do sometimes bend when I don't think they should have, and will generally bend on the shots that I expect is going to bend anything except those that are strong enough to make my "best braodheads" group.
Of course you have to consider that, to be a "best" broadhead I think it should rarely every bend on any impact with any animal tissues, from any impact angle. The top of my scale, the "best of the best" are those that "have shown no bends on any shot into any tissues of any animal", i.e. they have shown total structural integrity in all tissues from all shot angles.
In simple terms, I think that a few folks are going to have bends with the No Mercy on oblique heavy-bone impacts, even on whitetails. On perpendicular and near perpendicular heavy-Bone impacts I had no bends with the No Mercy; and I expect that MOST folks will find the same result.
Ed
TGMM Family of the Bow