Originally Posted by
70sSanO
The innovation that has really benefitted the average rider is index shifting, especially being able to shift while keeping your hands on the handlebar. Partnered with shifting aids, it takes the lowest level of skill to operate.
Moving the shifting mechanisms from the downtube to the bars is the kind of simple, low consequence thing that could be done in isolation.
Index shifting on the other hand - it might lower rider skill needs a tiny bit, but it's also another dimension that now needs to be kept in adjustment sending the bike to the shop. Most consumers wouldn't dare touch those screws.
But even if it's on your worthwhile list, it's again an inexpensive to initially implement, isolated change.