I guess you can say I stack filters all the time. I have a UV filter on the 24-70 f2.8 which I never take off, though UV filters dont really do much other than protection for the front element of the lens. But whenever I shoot cars I always stack a CP filter on top.
For rig shots I'm always stacking CP and an ND filter. CP to cut down on the reflections and at the same time by stacking the 2 it allows me to have a longer shutter. Especially helpful when doing rig shots during a bright day.
And for me I always shoot RAW, it just gives you so much more leeway in post.