AppMobi's DirectCanvas achieved all of it's performance gains purely through stripping a custom webkit Canvas element of its reflow processing.
Not really - it got its main performance gains by using GPU acceleration, since all they had to beat was the hideously slow software-rendered UIWebViews which didn't even use the GPU! That's how they got their advertised 5-10x speedup, which is about how much GPU rendering beats software rendering by.
My point about reflow is: the Construct 2 engine should never incur a reflow, except when you resize the window, therefore reflow is not important to the performance of Construct 2 games.
ur renderer is backed by OpenGL ES 2.0 on mobile, and WebGL will have a hard time competing with it.
I'm not sure why you say this, because WebGL basically is OpenGL ES 2.0. It's got some minor tweaks for it to work better on the web, but it's basically the same API. The fact our engine's WebGL renderer effectively makes OpenGL ES 2.0 calls directly means you can get a decent performance boost over canvas 2D, since it's skipping all the CPU work done by the canvas 2D layer, which can make it up to twice as fast. So supporting WebGL would be a good step for Pender.
rapping native api's to conform to open standards is also trivial
Really? If you take a look through the Web Audio API specification, is that really trivial to implement in native? Besides, why go to all the work of painstakingly re-implementing all sorts of web standards when it's already been done in Chromium, which is free for you to use?
I could give Pender a shot, but I'm sure it will run in to all the same problems we have with other DOM-less engines. The compatibility is just a nightmare. However if you come up with a Chromium-based wrapper that would definitely be exciting and I'd want to investigate closely!