Canon NB-5H rechargeable battery hack?

Does anyone know why the hack (covering middle contact of NB-5H battery supposedly "extends" battery life/charge 10x) described by the OP on this website works -- http://www.diyaudio.com/forums/showt...?threadid=7550 ? Has anyone else tried the hack? Are there any obvious dangers in doing the hack? Would I be risking damage to the rechargeable battery, camera and/or self by doing this hack?

I dunno. However - the way I'd look at it is that it may be there for a reason. I'm sure you'll void any warranty by doing something like this, and may damage the battery and/or camera as well.