If the author doesn't have an iPad then it's going to be a bit difficult for him to know how this will perform. Possibly he's just made sure it works OK for the 99.99% of people not using iPads.
On a contrarian note, a cross-platform game framework here could perhaps provide for remappable controls and performance tuning. This same cross-platform framework is labeled by Jobs as a threat to Apple's marketshare.
Perhaps Apple should not be so quick to bludgeon developers with claims of The One Best Way to the exclusion of all others.
But no, the iPad should conform to standards, and support those standards. If the iPad is not capable of supporting those standards in a usable manner, it's the iPads problem.
I think when one designs something like this, take cognizance that more and more devices have virtual keyboards.
Anyway, i really appreciate the effort. One step closer to a flash-less web.