I didn't think I was being vague at all. As I said in the initial post, perhaps the left
man-sau is pulled down or suddenly knocked aside, in such a way that remedial actions are not available to stop a simultaneous strike.
I also described the possibility of having no time or room to step, turn, or in some other way move yourself out of the line of attack before the strike lands.
I will attempt to illustrate what I mean over the triangle posted previously.
The black mark on the center line represents your right
wu-sau. (Maybe you hold it closer or further out along that line. Doesn't make a difference, as you can see.)
The left side of the triangle represents your left
man-sau that would originally be available to wedge or in some other way guard the space of the left facing right-triangle.
If it is momentarily unavailable to wedge or perform remedial actions, the area left of the center line is then left unguarded. The area you can cover has been reduced by half. You only have your right
wu-sau covering the area right of center.
The red lines represent incoming attacks through the unguarded left area.
If your right
wu-sau continues forward to attack on the center line, it won't stop the incoming attacks. Best case scenario is a double knockout.
So, you are forced to use your right
wu-sau defensively. It can't attack straightaway.
There are two options. The first is represented by the green line, where the right
wu-sau must travel across the center line to get wide to the outside of the incoming attack lines, and then track back to center to wedge them out.
There will be no time for this.
So, the only option is for your right
wu-sau to cross center chasing the incoming strikes with a
paak-sau as a last resort to avoid being hit, represented in gray.
In either of these cases, the response is indirect and inefficient, reactively crossing center to block, since a counterpunch is unavailable, and will likely leave you in an even worse position to recover and defend rapidly fired subsequent attacks.
The problem here is having an unguarded area left of center by momentarily losing your left
man-sau and occupying center with your right
wu-sau.
Occupying center does not help you, as can be seen.
Holding the
wu-sau further to the right of the center line only exacerbates the problem, leaving only the same options, but needing to travel a longer distance to achieve them.