who removes battery cable?

most any of the installers that i work with do this..  it is  a good practice to have and helps prevent any "problems" that you could have during install.

I always get a circuit breaker instead of a fuse for my power wire - so I usually trip the circuit breaker when I work on the car.

Removing my battery terminals is a *real* pain.

Yes as USAbuilt says, some new cars disconnecting the battery causes a ton of problems that the dealer only can fix. We had some chryslers (300, magnum, etc) when they came out if you disconnected the battery when you reconnected it a ton of lights were on and the car was stuck in limp mode. Not cool.

In 16 years I have hardly ever disconnected a battery before working on a vehicle. Only exceptions are when its absolutely necessary, like when pulling off a steering wheel or pulling out a seat with bags or sensors in them.

johnmax.... I like "limp mode" thats good!

I agree with USA, depends on what I am doing to said car. Big toonage etc. doors open for ever, cars around in the shop for a few days.... or more.

A deck and 4, or a simple 1 or 2 amp setup, an alarm/remote start, NOPE!  (how do you test anything with the battery unhooked?) 

99 % of the time i dont disconnect the battery. just use your head, simply put that if you ground anything power you may have issues. hook up the power last if you can and if you have to disconnect the battery they make memory savers that you plug into the wall and plug into the cig lighter with a 5 amp fuse that will blow first if you screw up. If you disconnect something like a VW beetle have fun resetting the security on the radio