I imagine it would be similar to de-borgifing which is a relatively new phenomenon. I think if we're talking about the physical attributes that make the Angosian soldiers unique, many can be once agian modified, but at what psychological cost? So, you've enhanced them, screwed with their mind, and now you're going to remove the enhancements - very difficult.<br/><br/>I have to admit there were A LOT of holes in that episode. I couldn't imagine how an individual could interrupt transporter signals, or even more unlikely mask sensors. I mean, they take up space so you could somehow mathematically compute the space in the area and note if there are disturbances. You could determine ambient temperature surrounding the individual.<br/><br/>These will be interesting engineering/bio medical questions we can attempt to answer that the writers of Trekdom just glass over ;)