Originally Posted by Eric Montgomery
I've never seen anything about kipping not being allowed for KTE or toes to bar--where have you seen it?
The CrossFit instructional video on Knees to Elbows / variations. It says (paraphrasing here) kipping perhaps could be used for times, but seemed to frown on it (even pointing out that the performer couldn't maintain proper form while kipping) -- and then spent the rest of the video showing bad kip form / stating don't do it.
In any case, the T-Nation article seemed to sum up what I was basing my question on: strict pullups require more strength and ~equal work. "Cheats" are not allowed in other exercises (KtE / BFPU's et cetera) and I'm just not seeing the logic behind kipping pullups as a replacement for strict pullups the way they are used in the WODs. [I certainly see other value in them, especially as someone pointed out, for learning MUs]
When I've had other questions I've seen some very good / logical / scientifically backed responses, but I'm not seeing anything resembling that on this topic. It looks like (to me) all the evidence is that strict pullups require more strength and at least as much work, but people do kips because "that's the way it is." (again, MU training not-withstanding)