I don't think it's really a "hidden change", but more of a correction in the skill description. I noticed during Dipladenia's event that Lilac's description had changed from the text about "movement alteration effects" into "ignores web nodes" as well, but both units ignored the whirlwind nodes as well anyway. So somewhere along the way, the description was altered, and now the change to the description was reverted again, but the actual mechanic of the skill never changed.

Whirlwind nodes aren't always beneficial either though, there have been maps where a "whirlwind path" caused units to reach the flagpole too fast, same thing as web nodes slowing units to reach some pest too late.