It's been a tricky discussion on an other thread, seems like if one says 'no tightbondIII for sinewing' it's being equaled with 'Ed Scott is a foul' ...or denying the holocaust (just to exaggerate it a little...)
See, I REALLY like what I have seen in the Ed Scott Video, and yes if I had a chance to follow that guy into his workshop for whatever stretch of time, I would! ...BUT I simply DO NOT BELIEVE, Ed glued that little sheephorn bow this anything else than the best hideglue he could get, or that thing would come apart!
I'm sure everybody would accept people like Lukas Novotny, Jaap Koppedrayer and Adan Karpowicz (have you seen Adam's book??) as being in that same bowyer's league than Ed Scott. Last year I had the fantastic experience of participating and translating in a daylong lecture about hornbow making held by Lukas Novotny over here in Germany; we were only 4 or 5 people, we really talked detailed, we inspected and shot some 10 or more hornbows of various kinds, finished bows as well as bows with the sinew laying open! These bows were some of the best bowyer's work that I ever held in my hands!!!
The question of TBIII came up, too, and I cannot repeat Lukas' opinion on that here, since it's really not in the family friendly corner.
I do not have enough personal experience with laying sinew for a final conclusion on the matter, but I believe that TBIII works, if the sinew is meant to protect the back, if the plan is to pull that back into a serious reflex, it'll be hideglue, hideglue or hideglue you can use.
JMO.
PS: I used TBIII to seal a snakeskin backing. When it got wet from rain, the surface started reacting RIGHT AWAY. It didn't come off, but it reacted.