what exactly does lenschanger do?

this is probably a stupid question but I've meaning to replace the aging 400b laser on my V4 with a 400c.

what I'm unclear on is what exactly lenschanger does to the eeprom. I'm aware of the mechacon bugs on later models, and I'm worried lenschanger is gonna retroactively make my machine... buggier.

or is the mechacon firmware stored somewhere else? is it even possible to patch it from the software side? or is it irrelevant because lenschanger doesn't mess with it?