I'm pretty sure there was a plan at the very beginning of the Jobs era, to get the Mac line profitable again just to keep the company going long enough to go after new and different product lines. About a year before returning to Apple, Steve Jobs even publicly outlined this strategy:

"If I were running Apple, I would milk the Macintosh for all it's worth -- and get busy on the next great thing. The PC wars are over. Done. Microsoft won a long time ago." -- Fortune, Feb. 19, 1996

http://www.wired.com/gadgets/mac/commentary/cultofmac/2006/0...