Just because a person does not actually see a converter's voltage change it certainly does not mean that it really isn't a poorly designed bottom-of-the-barrel "Smart" charger.
The WFCO sitting under my bed does indeed switch to 14.7 volts charge rate if the Lifeline depletes to 12.5 volts. It is utterly convinced 14.7 volts really is the factory rated 14.4 volts and the 13.75 volt mid charge is the factory rated 14.4 And the 13.2 float setting must be a waste of time.
Better yet, as temperatures slide downward into the 51 degree range, voltage slumps .15 volt. That is one finely crafted piece of cra...
...ftsmanship.
I find mentoring it, amusing.