I was wondering what the effect of allowing RF to use the same rules with soft targets (characters) as for Vehicles. Per ItS, RF against a Vehicle does not inflict extra damage, it instead inflicts a Critical Hit of 1d5 severity. Running the parallel with the Vehicle rules, True Grit would NOT reduce this Critical (it only reduces Critical Damage suffered after Wounds = 0). Since I only allow PCs and significant NPCs (friends and foes) to inflict RF, this shouldn't hit PCs too often, but it does help to keep RF from becoming "I was perfectly fine a moment ago, and now I'm perfectly fine red mist." Instead, it allows for all of those 'old injuries' and scars that WH40K heroes seem to sport.
I'm sure I'm not the first to try this. How has it worked out?