The idea is that you could write a SIMBL wrapper or an Xcode plugin wrapper (the API, though private, has been documented) around a subclass of the Xcode TextView (a dump of the framework - used to be called PBX.framework or some such would garner the class) and then basically do a poseAs.
I, for one, would certainly be willing to pay for this feature. That is, I already own TM, and I would happily buy another license for this product for $40. What are the odds, difficulties, etc of this?
vinayvenkatesh