Need advice on tub overflow--do I even need one?

Hi, I actually posted my question over in the code section but thought I would run it by you over here as well.

A MN inspector told us we need to install an overflow in a 1960 custom-built tile tub. Aside from the fact that my plumber isn't sure about drilling in to the ceramic tile and whatever's behind it, I'm wondering if we even really need to do this. I looked it up online and there seems to be some controversy in the plumbing codes.

Thoughts?????

(Photos in the thread I started in the code section.)

Not sure about the code, but you can make a nice, clean hole without messing up much with a diamond core bit (essentially a piece of pipe with diamonds on the end and a shank on the other for the drill motor). Now, a diamond core bit in that size will not come cheap, but you don't need a super long-lasting one as once you get through the tile, the backer is pretty soft and it should go fairly quickly.