Wouldn't you need a vision mixer (or IP equivalent) dedicated/available to each destination Playout for any processing of a video signal (i.e. fades to black, dissolves etc.)? That's more functionality than a router cross-point would allow (which would be cut only)
I wouldn't be surprised if some aspects of regionalisation didn't get that level of sophistication and instead got 'cuts-only' transitions (which can be handled much more easily at a router or IP-equivalent level)
If they're changing sources on the router, then yes it would only be able to cut.
Playout chains are usually designed to have a more capable master control cross-point for each channel, so I've assumed that ITV have followed this for the regions and aren't doing cuts on the router, but I agree with you in that I wouldn't be surprised if they haven't bothered. In UTV's case however I would have thought they would have one, given how much local presentation it broadcasts.
Considering that the ITV transmission facilities aren't that old, and that every region has to have its own video server and basic graphics capability for the DOG
(assuming it's inserted regionally, which I think it is), I would have thought they'd use an integrated channel device to playout the regions, such as SAM/Grass Valley's ICE. If so that would have full master control cross-point capabilities.
Like I say I'm not sure of the exact setup for ITV, I'm only going off the bits I've seen/heard, so I could be totally off the mark.