Insanity will be interesting to say the least. Diego has a dormant darkness and with problems. Despite this, he has a strong will and personality. So while he can be insane, his will demands he still does things his way. It just happens that his way happens to be good. That and he never really udnerstood much of doing evil (well, outside of kinda like being drunk, but that would require Diego not being in control and not being him... it's kinda complicated XD)