Fact or fiction.... Not turning off A/C before ignition is bad......

I've heard that not turning the A/C off before turning off the ignition is bad on the compressor. Is this true or false?

Out of all the vehicles I have ever owned, I have never done this "supposed" requirement and the only A/C problems I have ever had are, to my knowledge, caused from other issues.

My car, because I once overfilled it while topping it off with refrigerant and had to bleed some of it off, and my pickup because, due to it sitting for so long and not being driven while we were out doing the OTR thing, the refrigerant must've leaded out somehow (like tires will do when the vehicle sits for long periods of time) and since it is being driven every day again, we haven't had any issues with it. It still has the same amount of refrigerant that I put in it over two months ago.

Just curious what everybody has to say on this and if there's any documentation or proof that supports this practice, thanks.

 

One of the other things I was told that happens when you don't turn the A/C off prior to turning the ignition off is that the high pressure refrigerant gets trapped in the preasurization chamber in the compressor and has no where to go, and eventually finding its way out of seals and o rings. I figured if the stuff found a way out, then you have a leak and that you need to get it fixed.

Maybe I'm wrong here or just don't know exactly how the air conditioning system works on a vehicle but what seems to me is, whether you turn the A/C off with the switch or turn it off by killing the power to every thing with the ignition switch, the same end result happens...... The clutch on the compressor disengages and the internal workings inside the compressor suddenly stop so, there will always be trapped pressure in there unless there is a way the pressure bleeds off while the motor is running and the compressor is disengaged from the serpentine belt so, I dunno.

 

That would, in a way make sense but like it was mentioned already, when you start the ignition, the switch, or something in the vehicle kills all the power to the accessories while cranking the engine and when the engine starts, power is restored to the electrical components that where shut off.

It seems to me that on older vehicles with older technology is when following the complex list of do's and dont's really apply.

Maybe newer technology takes out the human element and protects itself rather that relying on you to do it.