Its basic safety, you don't hold a knife out to someone with the blade first. But it making him appear non-threatening is also good. He blinks when the blade is offered back to him but takes it and moves to get a better look at SecUnit's arm and the remaining husk.

"O-okay..." He takes a moment to study it, so he can figure out what the best angle is to go at it, before starting where SecUnit's noted. He's not sure how tight the thing is on there, or exactly where the husk meets the skin, but he tries to stick the knife in right at that point.