He may instead have judged that he still had sufficient height to complete the loop (and of course he was very close to being correct).
Indeed you are probably correct DRUK, which I'm afraid means he shouldn't have been in that particular cockpit in the first place. If you miss a critical gate height by 1000ft or so and then decide to continue regardless then you shouldn't be a display pilot. How could the Shoreham Display organisers possible have allowed for such an eventuality?