@ de facto...
"At minima vis (lets say 550rvr)..."
Who begins or let alone completes an ILS with the RVR reported at 550 feet (or are you talking meters)? Don't most countries have an approach ban for the visibility for Cat I and Cat II ILS approaches?
"That brings me about cold weather corrections.....how many unknowingly bust those minima cause they dont know or too lazy to make such a correction?"
Many I'm sure. I suspect pilots that do not operate in the cold weather environment are not familiar with the temp correction procedure.