He was one of those guys who made ST with his classic lines. He played a helluva Scotsman. He was also very appreciative of the attention he got from fans. So much so...in fact...that he attended a ST convention(his last) last year well into the onset of symptoms of Alzheimer's. He could only answer with one or two words when asked questions. Howard Stern was playing it back on his radio show while making light of it right after his death which was, of course, distasteful. He was a good guy who didn't mind it when fans would throw back his old quotes at him on the street. - Surf "I'm giving her all she's got but I don't think she can take much more."
I guess he just didn't have the power. RIP Scotty...you were perhaps the only "cool" Star Trek character.