So am I the only one who watched the pro riders stick their tongues out on hard climbs, and decided it could work for me, too? It does.
If you haven't done it, try it right now. Yes, sitting on the couch watching the Tour, sticking out my tongue just to see why they do it opened my airway in a major way. So it took me exactly no convincing to stick my tongue out when I'm climbing.
Downsides:
1. I look stupid to oncoming cagers.
2. I drool on my knees.
3. I hope I never suck a bumblebee.
IIRC the pros do it on sprints, too. Not that I race any more, but I'd be way afraid of biting my tongue off at high speeds and close quarters!