What I meant, is that the question is made more complicated because it is harder to test whether the system is functioning properly.

If a wireless transmitter fires the flash at the wrong time with a focal plane shutter, the entire frame won't be illuminated - this is easy to see in a test exposure.

Whereas if a wireless transmitter fires the flash at the wrong time with a leaf shutter, the entire frame may very well be illuminated, but the exposure may be less, because of the shutter not being at its maximum opening. That is harder to verify in a test exposure.