If you are just doing the coping then I agree pouring concrete is overkill and the clear stone will work well. If only 2 inches overhang it should be good. But if you are thinking of continuing brick beyond the edge of the coping then imo concrete will work fine. The way we spec it is sono tubes at 6' apart 4' deep and 4" poured concrete w/wiremesh. This is how we have been doing it and to now I haven't had any call backs. This is a pool that was done in 08 and what we did was put a smaller coping (8" vs 12") then poured concrete to 30" around 3 sides and 12" on the opposite. Its held well. This pool was built in 1970.