I'm really ignorant on the subject, so tell me if I'm wrong, but am I the only one to be puzzled after reading this statement?
Couldn't he have been able to test this thing a little earlier?
I was thinking the same. Wouldn't he have had to run sections along the way to make sure they were working the way he wanted? Certainly should have run the game a few times over the last five months or so otherwise he could've wasted the whole time programming a game in a new engine that wasn't up to the task....
what you both say is true, he most likely did test along the way but he possible means how the finished game will run.
Considering the last few items moved to 100% completion pretty fast, he may not have done any real testing on them, and he only covering himself encase there is bugs.
I do that with programming, say not 100% sure how it work , even though I pretty certain it should work , but until you actually see it finished and working you never really know for sure.
however, am just guessing this is what happened, got no real clue.