or popping toggles and immediately doing a braked turn
No. Popping the toggles requires the jumper to get a grip on both toggles (and despite your BASE jumping desires, most skydivers do not use big grab toggles), and then it requires both brakes to release cleanly or you have just made two problems out of one. You started off with an imminent canopy collision, and have now added a canopy with a comprimised control system.
The rear riser turn can be accomplished with a grip anywhere on the rear riser, and will result in a more effective amount of response vs. the amount of input required. Pulling a toggle only effects the tail of the canopy, while pulling a rear riser will effect the entire back half of the canopy.
Another advantage is being able to grab the rears while keeping your eyes on the traffic hazzard. If you have to look up to grab your toggles, you're not watching the guy you're in a rush to avoid. It's much easier to grab the rears sight unseen, while continuing to watch the other guy.
Back to your BASE intentions, check with your mentors, and they'll tell you that rear risers can be used to turn, brake turn, stall turn, or back up your canopy if you open facing an object. Again, quicker and more reliable than going for toggles.
All this is true, but you can still fly your canopy using harness imput long before you can reach risers. This is not a "one or the other" answer.
Many tools a box should carry?
(This post was edited by skyjumpenfool on Aug 21, 2012, 9:51 PM)