10 seconds is pretty good considering:
- poor weight distribution/transfer. The bike doesn't look even close to lifting the front wheel.
- smoking launch on a cold tyre
- no "hook up" till at least 1/2 or 3/4 track
His bikes were clearly never optimised to run great times. They were designed to put on a spectacular show and succeeded magnificently.
I think that the bike would be (even more) terrifying if it was allowed to hook up off the line. In the video he appears to launch from the bare concrete off to the side of the usual start area. Attempting to launch a direct drive bike like EJ's from the normal glued-rubber surface would be exciting in all the wrong ways.