I respect that the PHP maintainers recognize that it is not enough to accept a working JIT implementation - they have to understand and maintain it. Speed is one thing, but long term maintenance is more important.

> use DynAsm (developed for LuaJIT project) for generation of native code

But at the very least, this exercise will ensure that DynAsm will be actively used by a few people. So even if this PHP JIT effort fails, the underlying JIT technology will be more widely understood and hopefully better documented for other projects.