This is not uncommon for many doctrines, players can go whole matches without choosing a doctrine until the end.
The only effective use of the ability was when JibberJabberJobber got its 2 shermans at half health stuck blocking each others pathing and colliding with the munition cut off flag, and he still managed to save 1 of the 2 by retreating in time.
No offence, but it seems that you completely missed the point why I posted that particular video.