Being able to unweight your rear wheel, or even 'bunny hop' your bike into the air is a damn handy trick for flying over gnarly terrain like rocks, water bars and greasy tree roots.
Off road riding, especially the fun stuff, invariably involves navigating over tricky obstacles.
The techniques described here are intended for the very steep but the same basic principles apply when attacking more gentle gradients.
Even if you've got an old clunker - you'll weigh considerably more than it does. A typical rider to bike weight ratio is around 6:1. The obvious implication is that the position of your body on the bike has a major effect on how the whole arrangement performs.
The correct interface between rider and bike is a crucial foundation for developing good, or even great, riding skills.
Good off-road etiquette is clearly in the best interests of mountain bikers both as a group and as individuals - reducing track wear 'n' tear, bypassing damage to yourself or others, maintaining good humour amongst various user groups, and continued access to appropriate shared-use tracks like the Queen Charlotte and the Heaphy.