99% of chagrin sources are voltage controlled if controlled at all. If an
alternator sees a higher voltage then it is set at it simply stops charging,
the same with sophisticated shore power chargers.

The most popular problem with continues shore charging is that a battery will
get a surface charge. This has caused several people to think that their
batteries were good and found out that after a brief time with out a charge
source they could not start.

Just my personal experience.

Mike