The standard reference for "pointer warping" for Tk has been the "usage FAQ" [L1 ]. It briefly mentions that pointer warping is a bad idea, supplies source for an extension which implements warping, and also points to ..., with its implementation of the same as ... The FAQ doesn't seem to be current ...
As "Changes in Tcl/Tk 8.3" hints, release 8.3's event command builds in pointer warping.
Among the legitimate uses of pointer warping are test automations, including Android, and for pedagogic purposes (Android can also help build demonstrations).