Ditto...

If racing, all slop is bad. But, it's a Hobie 16, and there's only so far you can go due to the design. It's almost impossible, even with a glued boat, not to have at least some amount of independence visible as the bows travel across the water, particularly if it's rough.

If not racing, slop is bad if it leads to further damage. You don't want the boat to be wearing itself out as parts rub together. If you see movement, it is best to try to reduce or eliminate it, so that you don't wear away material that may be difficult or impossible to repair without major work or expense.

Hope this helps.

Mike