They have me on so many drugs to kill the pain, it is no surprise that I am not being clear.

Roughly 2% system OIL capacity loss is what I was trying to say.

The loss of system efficiency due to changing to the less efficient R134a molecule is widely accepted as about 15 to 20 percent.

In general; that is true, a very skilled climate control mechanic can achive only 13% loss.
This is not possible in a general shop environment, it takes too much time, effort and training.