Found on Memory Alpha:
Of returning to play Mendon, Putch recalled; "I was all very impressed by that. I thought, 'Ah, they love me, they love me.' What they really loved was that it was me, because they'd spent all that money on making that blue head and it was form fitted to me...I don't fault them for that. I would have done the same thing, but it's funny how you are naive about these things when you're just an actor.