I don't dissolve calcium hypochlorite first. I pour it into the pool in the shallow end, all in one spot, then use the Wall Whale to brush it up and around. It swirls over to the deep end pretty quick. Probably better to do that in the deep end and I used to do that, but in the shallow end I don't have to extend the pole and the pole is stored at the shallow end -- call me lazy.
Second, I'll guess that the pool store is suggesting to you that you need to "shock" your pool with one of these products each week? Here at TFP, we only shock when the pool NEEDS shocking, as in visible algae, increased chlorine demand suggesting invisible algae, or some sort of emergency like when I saw vultures sitting around my spa, leaving awful bits of "something" floating in the water. When we shock, we do it at a specific FC level and until specific indicators tell us that we are done. It may take many applications of chlorine over many days to do a proper shock.