I follow along with what Pat stated, and restating what I have stated before below.

On the Dutch side we tip based on the 15% to 20% usually the 20% and as also stated in this thread if Happy Hour we likely will tip at a higher rate. "IF" a service charge or whatever is added to the tab we consider that part of the tip, and not my fault if that does not go to the wait staff as that is a management issue and the employees issue that chooses to work there. Lots of jobs for good wait staff on island.

French side, 5% is our norm to add although we often end up at 10%.

I completely understand why some places add the line item for a tip/service charge as some nationalities don't tip or tip similar to what the French side norm is. If on the Dutch side and wait staff depending upon that for part or most of their income that is not really fair to these people, but it needs to be clear, not hidden and when they argue then that is my last trip there.

It is all pretty simple in my opinion if you apply what I just wrote, took me years to get comfortable with the French side ways but have not had a single issue and always felt welcome when returning. Speaking of returning, 17 days until our longest stay yet which will be 4 weeks! Whoooop Whooooop!!!