That is quite true. This bag would be targeted at a certain type of user. I came up with the idea primarily to maximize volume for those flying on aircraft with very small overhead bins, such as the Embraer and Bombardier regional jets. A smallish carry-on that could carry a relatively large amount of stuff and slide effortlessly, yet snugly, into a RJ bin. As I mentioned before, quite a few FA's have seen this and looked oddly at it, then when it slides into the bin as perfectly as a glove over a hand, they start asking questions.

Your comment actually leads to the point that I was addressing. A 22" X 14" X 9" bag is not designed for an aircraft bin. I am talking about a bag that would form-fit a bin. So it would not be a Cuboid, as most bags are. It would be a shape specifically designed for a smaller bin. Then, of course, it would fit easily into full-size bins.

I came up with the idea when I was based out of an airport that only had RJ service connecting in a hub city, missing a couple of flights because it took 20 minutes to get my "carry-on" from the gate check. The idea is to have a bag that fliers who regularly fly on RJ's could have, that they would not have to gate check.

You are correct, this idea does not work for a bag that is designed to fit full-size bins such as most B737 series aircraft. It's just too heavy. However, I did consider that a version for those anemic B767 center bins might work well.