True, but it is unclear at certain angles. The shotgun trooper in the top room would be far harder to see if he were directly adjacent to the wall below him. It's also partially a clicking issue: the transparency makes it difficult to see which square you're highlighting when mouse-selecting a trooper close to a wall that obscures view. The same selection-flicker sometimes occurs during targeting too, in my (fairly limited) experience.
Can't say I have any suggestions beyond highlighting the selected square better, or maybe more fade on the obscuring wall but even that's not terribly helpful and I don't know if it would do any good. But that one bit of the controls is still fuzzy at the moment, in a way the rest of the combat controls aren't.