I agree with the comments about Portnoy. His playing has stopped progressing after SDOIT i think, and indeed i know exactly what he will play 90% of the time these days.
Happened with LTE3, new NMB album, and pretty much all his projects ever since he left DT.
This is why i'm also happy to see that drum production has been improved on DoT and the upcoming album, because MM's playing has been so underappreciated, and there's a fault to the production as well, many of his embellishments and cymbal work went unnoticed in the mix. Seeing him perform live gave me a new found appreciation for his dynamics and ideas.
Now for Petrucci spreading himself thin creatively, i think that's not the case, he has some great ideas, but he's not really pushing the boundaries like he used to do back in the 90s, fusing jazzy/fuzion elements. He has more or less been set in his style.
I also think this has to do with age and the range of influences he has at this time.
@Glasser, i was wondering from a technical point of view, is there a level of complexity in the album similar to what we heard in The Alien? Are there any mind-bending instrumental parts?