he's a freekin moron
keep the spare but
tie it down, that 50 pound tire hitting you in the back of the head in a accident aint gonna feel good
That's exactly what happened to me (that might explain a few things!). I had mine cable-locked to a D-ring in my old Runner, I got rear-ended at a stop light and the tire broke the D-ring and mashed my noggin! She was doing about 55mph!
EDIT: Oddly enough, the tire was a BFG 32x11.50!