Gravitation beam cannot be deactivated

Even after deactivating gravitation beam in abilities menu, phoenixes continue to use it on different crapy units. may be deactivating just breaks after first manually use of beam, dunno, but anyway - it stops working, and usually even insane massing of phoenixes can't provide u enough birds with not spended energy to break just a few infestor's mind controls, but u can be sure that no enemy marauders keep standing on the ground...