Do you fully tighten battery cables?

[TugOwar]

I know this is gonna sound really screwed up to some of you guys but please bear with me for a minute.

I've driven old chevy trucks for most of driving life. A 66 1/2 ton in particular that I drove for 12+ years.
Over the years I've had the occassional wiring problem. Once, on that 66, a main wire that runs from under the hood into the cab (don't remember which wire it was) shorted and burned completly from end to the other. Because it was encased inside the harness it took several other wires out with it. Needless to say I spent many head scratching days tracking down and rewiring the damn thing.

After that I got in the habit of leaving the positive battery cable a little loose on the battery. Snug but loose enough that I could pull it off quickly without the need for a wrench in case of a short.

This morning I get up, sh!t, shower & shave, and get dressed to go job hunting. Jump in the truck and hit starter and &%$#@!, dead battery. Apparently the positive cable had gotten looser and dirty and didn't have enough contact to keep the battery charged. DOH!

So I guess I'm looking for your thoughts on the matter. Is it stupid of me not to completely tighten the battery cables?