It's actually very likely I have to write it. I write compilers. Hence the hatred. I would seriously choose x86 ASM with all the backwards compatibility quirks going back to 80s any day.
Well, if you're interested in compiling to something that runs in all browsers, you have to compile to JavaScript anyway. Given that, asm.js is strictly an improvement over the current state of affairs: the rails to stay on for high performance are well defined and (hopefully eventually) cross-browser.
The alternative is to try to make a clean break from the past and forego backwards compatibility in the name of a cleaner encoding, so that compiler authors can generate object files with nicer syntax. That sort of thing been tried many times in the history of the Web and usually hasn't ended up succeeding. For example, take XHTML 2: despite the fact that XHTML 2 was hugely cleaner than HTML 4/XHTML 1, it never got any traction and was abandoned by the W3C. At the scale of the Web, practical considerations end up dominating engineering considerations.
