JPB;
Bleed through can be a problem if you are stretching the dough very thin and not applying a light film of oil to the skin before saucing. It can be a problem resulting in a gum line on just about any type of skin/crust if you allow the dough to set for an extended period of time after saucing (again lightly oiling the dough helps here too). My dough weights for a 12-inch pizza go as low as 9.5-ounces and I've never had an issue with bleed through even when the pizzas are staged for a few minutes prior to going into the oven (this is with a decent sauce that isn't separating), and when I'm using fresh tomato slices as I typically do at this time of the year I ALWAYS lightly oil the dough skins prior to application of the tomato slices.
NOTE: Bleed through tends to be more of a problem with doughs that do not contain any oil/fat that with doughs that contain 1 or 2% oil/fat, this is because the oil in the dough helps to prevent the migration of moisture from the sauce/toppings into the dough before, during and after baking.
Tom Lehmann/The Dough Doctor