The easiest thing we have found is a snub-nose small embroidery scissor - and we SNIP the back leg joint (at the knee)
Since we sometimes feed as many as 10,000 crickets a week - this is by far the easiest way to disable them. We sit down to a bucket and grab, snip and drop in the next bucket. It gets routine after a while.
Morgana - Reptayls, Ltd.
:Tearing the legs off can be a bit messy... all you have to do is pinch the leg of the cricket and it normally pops right off.