Quote Originally Posted by DennyW View Post
Just look at all the fun we just had though.
It WAS a "lively" ... discussion! Wasn't it?

It has always been an unwritten rule when working around batteries to disconnect the negative FIRST! The reason for that is, should your wrench touch the body, you won't have a spark when you touch the grounded metal and possibly cause the battery gases to explode.
(when I was in vocational high our teachers would insist that we place a folded shop towel over the positive terminal to further prevent any possible connection of positive & negative! It's a practice I still use!)

I don't believe it has anything to do with your switch manufacturer intending anyone to insert the switch into that side of the circuit.

Everyone is correct tho' in the most common and some sanctioning bodies rules is to require the Positive side to be interupted with the switch.