Because of different wall thicknesses between type L and M copper tubing can compression fittings be used on both types?

Thanks Bill that's what I was hoping to hear.

Because type L copper tubing has a thicker wall than type M all of its dimensions cannot be exactly the same as type M- It either has to have a larger Outside diameter or a smaller Inside diameter. The responses which I received to this question (here on Yedda and also asking around elsewhere) have been consistant in stating that its the inside dimension which is affected by the thicker wall. Type L and M have the same outside dimension but type L has a smaller I.D. than type M. This also means that various connections such as "Sharkbite" can be used on both.