i dont think itll work, as there are a few governing factors here.
1. fuse blow speed
2. 10mA is enough to stop your heart
3. resistance b/w foot and ground would be in the mega ohm region
fuses typically are designed to blow within minutes, some more, even quickblow fuses will take a while to blow, while the damage is done.
and 80mA fuses are uunheard of i think, unless specially made or somthing, and these wouldnt break in time. the fuse works by heating a filament up, like a bulb, and when its hot enough the steel/tungsten i think filament breaks, 80mA aint gonna melt it!
i dont like the being earthed to the guitar thing, so i bought a pair of active EMG's which dont earth external parts, so its safer!
hope this helps
mike