Does adding flour before egg coating and breadcrumbs help sticking?
Yes it is helpful for an initial dip in flour...as it would  help the egg to stick better...
A little addition of oil in the egg also helps thin the liquid coating,  with the extra fat from the egg will help brown the breadcrumbs better underneath. The proteins in the flour and eggs help the bread crumbs stick to the food once cooked. A fabulous and crunchy crust is formed around the food once fried in a pan.
 Do let me know if my answer is helpful