Timing changed after Cap + rotor swap?!

im speaking about the 2 snaps that hold the cap on the destributor, they have a little play in them, allowing for maybe 2 to 2.5mm play in them each way, making a total of 5 mm play (for the americans here: thats 0.19 inch of play on the cap rotation with the snaps on) i know this doesnt account for much ignition timing.. but still..