For whom?
For programmers?
For Vim users?
For Emacs users?
For Photoshop users?
For writers?
For English writers?
For Non-English writers?
For Mathematica users?
For LaTex users?
For my mother browsing the net on her iPad?
Everyone has a different use case, programmers use special characters more than non-programmers, Vim users use different shortcuts than Photoshop users, C programmers use the semicolon while Ruby programmers don't, American writers use the letter y more than German ones and so on. Claiming 46% less effort than qwerty needs further clarification.
Another thing which comes with all alternative mappings: you need to be able to change all your devices (desktop, mobile) to your new mapping, otherwise the constant mental switch from one to another keyboard layout won't bring you any speed and flow improvement. My writing speed goes down to zero when I have to write on a British layout (which is already super close to the US layout compared to other countries).