"There's not a one of us in this world, even the luckiest, whose path is entirely straight and without obstacles. In this unfair world, the test of your existence is how well you do in this unfair world."

Of course shutting up and multiplying, always advancing forward and doing the impossible is the way to go. But as said, the test of instrumental rationality is whether or not you succeed at what you've set yourself up to.

If rationality is being signaled for intellectual honesty's sake alone, or maybe pride, then this signal may not correlate with real world results, and is pretty vain.

By that I mean, that, for instance, I'm not above self handicapping myself, playing possum, and using other similarly dirty tricks, when I think that it'll help me further my goals eventually. If lightly self handicapping yourself, and playing that card, helps you receive help or advantages in excess of the loss you incurred because of that handicap, then it is instrumentally rational to self handicap.

Doing so isn't risk free. You may end up believing your own lie http://lesswrong.com/lw/4e/cached_selves/