Do you mean "tether block" as in you can't download the app from the market or that tether apps don't work in general (ie APK's of ET/PDAnet installed from "other sources")?
Over on XDA a member posted about using his Rezound with PDAnet, "I downloaded and installed it and it works great. Immediately went and purchased a license for it. Thanks!"
I tether quite often with my Incredible and the simultaneous voice/data on the Rezound would make tethering so much more flexible (almost bought a thunderbolt a while back for this exact reason).
Getting close to pulling the trigger on a Rezound, but this kinda caught my attention =)
BTW, I thought my Incredible had a fairly nice screen until I put it next to a Rezound =/