use of Mending spell for ship repair

could someone please clarify or extrapolate on the rule from Concordance
about using the 1st level wizard spell Mending to restore hull points?
The way I interpret it is that it is a permanent fix to the hull.  Isn't
this a little powerful for a first level spell?

I am new to the Spelljammer world and am attempting to hammer out some
indescrepancies in my campaign.  It seems that with this spell, a ship
would never be found in bad repair or damaged, as long as they had a
legitimate Wizard on board.

Thanks for your time

--Grimwulf
slvf5@??.???.edu

"I am the greatest swordsman that has ever lived!"
--Madmardigan