Basso tried to have an adjustable seatpost in the 2011 Giro. (a much simpler mechanism than this proposal) That caught on like a chocolate teapot.
Ha ha! I want one of those posts!
To be fair to the company, I think it was something that Basso just wanted for himself, rather than a product that they really thought was gunna sell tons of.
I would pay hundreds of bucks for one. In search of one, I started a thread about them (here, I think), and even emailed FSA, but had no responses.
I'm one of those dudes who always adjusts his seat height, mostly because my lower back is a bit dodgy, and the difference between what feels comfortable on a good and bad day can vary up to 7mm! I also like to be a little lower for strong head and crosswinds.
Sorry to hijack the thread there for a moment.
The "changing crank length" is something I might be interested in, provided, of course, that it was 100% reliable, and without creaks, clicks or any perceived movement in the arm. I imagine extra weight and cost could be an issue. I like having longer cranks for off-the-saddle stomping, so I reckon it would great to flick a switch and have 185mm to sprint over to a breakaway. Seat height would also be an issue, because almost all people adjust the seat height for a different crank length