Capri Bracing Questions

[johncorth]

So, I've been looking at Capri pictures lately and noticed this one showing the internal bracing of a Capri:

Now, I've noticed this cross brace through the slash sound holes before and always assumed that it was just a back brace since that's what it looks like through the sound hole. Only recently did somebody (libratune) explain that the brace is attached to the top, but is just notched out at the sound hole (in the earlier ones where the brace went under the sound hole before they moved it behind the sound hole). So I assumed that it was akin to a sound post that connected the top and back, sort of along the lines of Gretsch's trestle bracing. But looking at the above picture, it seems like the brace doesn't go all the way to the back. Are my eyes deceiving me, or does that brace sit a quarter inch or so off the back? Is it only connected to the top and sides? If so, isn't that a strange and ineffective brace? I'm not understanding the purpose of this design.
Second question - when did Rickenbacker switch to X bracing?
Third question - for those who've had Capris with both this cross bracing and X bracing, can you say whether there's any notable tonal difference between the two?
Thanks!

[chefothefuture]

The cross brace is more to prevent the guitar from
splitting.
Not all Capris even have the cross brace and some have it
perpendicular to the direction of the laminate.
Given its bulk, there did not seem to be any reason to
have it connect to the back.
Though I had one that had shims stuffed in there to prevent rattle.

[johncorth]

Thanks for the reply. That makes sense. I couldn't see how it was much of an effective brace, but I do see how it could hold the body together.