andSo far the only solution vie found is the MyWi app on the jailbroken cydia store. Gets excellent reviews but I would prefer not to have to hack my iPhones OS.
and this related to battery use:Jailbroke my iPhone, now running Cydia & MyWi and it works like a charm. Well worth the $9.99 price.
Those seemed to answer your question quite well, I thought. Or were you looking for more? Different? What?Actually, I find that using MyWi uses relatively the same amount of battery to tether as using my iphone to surf would. It obviously uses more power as it is using wifi, but the fact that the screen is off balances things out. I use it to teather my MBP every day on my 40 min train ride, and my fully charged battery is at about 80% at the end of the ride. That is roughly the same reading I was getting when I was using my phone to surf during the same trip.