Panthers will have harder time getting vet if they are fighting 100-150 fuel tanks then if you've used it against 180+ fuel ones.
Thanks for formulas, hoverer it still problem of large hp pool on top of low cost of churchills.
If you want to vet quickly on churchills, simply use StuGs or JP4 as panther will not be most effective in both, getting vet or even being a reliable counter as its designed to fight high armor targets, not high hp ones.
Only panther i use with OKW is cp, however jp4 and cp for mark target spam have one of the best AT synergies in the game. Still, they take too much time vetting on churchills. Its just wrong.