Is the insert you are describing kind of like a drywall anchor? It sounds like they are screwing in a larger diameter fastener to get good mechanical grip (and some chemical grip if adding epoxy) and then fastening the double chicken straps to the anchor.
The anchor sounds like a pretty slick idea. But since I hadn't heard of that or thought of it before, I installed the kind of inserts that Remi described. I encased them in some high density foam for extra durability, as described by the "board lady": http://www.boardlady.com/extrainserts1.htm
Here are some more details on what I did with my HWR: