A get-out-of-jail-free card .. certainly not an efficiency bonus, though .. if held ridiculously high, pitch up with boards .. gear down .. dirty up (below max flap level) .. and then go down at gear limit .. subsequently approaching the appropriate flap limit speed.
Good for bringing the 737 back to better than a mile a thousand and got me out of trouble on a couple of occasions in years gone by coming into Sydney with traffic problems keeping us very high initially.