Yep. Well, see my managed time paper; basically we use no fancy algorithmic tricks and it all works out fine. There are 2 ways to do incremental parsing: the hard way based on some fancy delta algorithm, and an easy way based on simple memoization and conservative recomputation.
Academics especially often over think these problems when the simple solution often works fine, and performance wise you'd have to mess up pretty bad before parsing becomes a noticeable bottleneck.
As if the former would require less math than the latter… Really?