With routing, I often use cue sheets that are by road to help navigation, especially where GPS can be a little off or some of the intersections around here where there are 6 different ways you could turn right. If I route from Memorial Drive @ JFK St to Central square, along JFK St, Mt Auburn St, and Mass Ave, the cue sheet ends up being
* Turn right
* Keep right
* Slight right onto Massachusetts Ave

In places where the drawn cycleway repeatedly enters and departs from the road, it makes the cue sheet very noisy.

I take rather the opposite view from you, if we tag every flex post protected lane where the flexposts have been run over enough that they aren't remotely white anymore the same as the Somerville Community Path, I see that as much more degrading routing. Flex posts don't offer the same protection as hardscape.