While I can understand the comments about Dylan's performances these days (I said long ago in this forum that he can be a hard listen these days and that his performances are less consistent than Mark's), I think you're taking a very short-sighted view.
What you got were over 30 Mark Knopfler performances that you wouldn't have got but for the Dylan tour. Even if, from your limited perspective, you regard them as half-concerts, that's more than 15 additional "concerts". As an extra, you got Mark contributing to Dylan's set at a number of shows. That, initself, should have been of some interest to you. You also got "early" versions of some new songs, which may well be changed by the time they appear on studio disc and in any later shows, giving you the chance to see how he develops his songs over time. And that's not to mention the question of the "motivation effect" of the shows on Mark, as mentioned elsewhere in this thread.
Even to take your view at face value, the "price" of this was a possible delay in the release of Mark's new album (as nobody is really sure when he would have finished and released it, had he not toured with Dylan, so there might have been no delay) and a delay in the resulting album-supporting concerts (ditto). Irrespective of their date, Mark's likely to be doing these concerts anyway, so that's not a real loss. You may have "lost" a soundtrack album but even that is far from established.
I think that's a pretty fair trade-off. Glass half-full or glass half-empty?
Incidentally, in January and February 2012, Dylan has set to in Jackson Browne's Santa Monica studio and recorded his own new album. One rumour was that MK would guest on it but, as the dates seems to clash with Mark's own post-recording activities, it seems unlikely - unless he phoned his contribution in, of course.
