I wish I was in a position where I could post a few pictures, but I would say "sometimes". I guess it depends on your definition of "completely".
Can conditions make my Butch T plants start spitting out Yellow Bhuts? Definitely not.
Can conditions cause my Butch T plant to start spitting out pods that look like an orange hab? Yep, seen it happen a few times. They still taste like a Butch, unfortunately, and are hot as all get out.
When I move plants into the greenhouse at the end of the season I almost always get a round of pods that look nothing like the pods that grew outside, but it is also an extreme change in environment. Outside my red bhuts are pimpled and gnarly, inside the same plants produce pods that are straight and smooth. If that fits your definition of "completely" then there you have it.