The first thing that they taught us at orientation at the consulting company that I work for was to stick to one airline because it will help you in the long run. However I just hit Delta Diamond and am strongly considering using corporate status challenges to another airline and keeping elite status on two airlines.

My company has a very flexible travel policy (in economy of course) and we can choose carriers freely and fly anywhere.

Anyone have experience with this? I know it sounds like blasphemy, but your thoughts?