To address a few of the comments and various points sprinkled through this thread:
One of the things MM may be expressing is that if his role were to expand, as he clearly has more to contribute, then we, as fans, would experience the full value of what he can bring to the table.
MM “tailored” the demo drum tracks of ADTOE in the recording process because some of what JP laid down on a machine was simply not natural to reproduce by a living person, the parts needed to be transcribed into something actually playable.
His shifting the emphasis of his body from left to right depending on key changes is an intriguing concept and I will listen for these stereo subtleties more closely.
Another area which may have been addressed is publishing credit – or in other words – who gets money if a song is licensed or royalties are earned. This is a sensitive subject for many artists, because beyond the pride of authorship, it also establishes who is entitled or precluded from future royalty payments.
I need to check the DT13 guitar tab book which definitively lists publishing credit for each song, but my recollection is that he has ZERO (0) publishing, which could be a sore spot. Even if MM contributed original parts, they may not have qualified as copyright protected composition, as most drum parts do not, and/or JP didn’t think they contributed enough to garner publishing (again, I need to verify the actual credit though).
Once upon a time, Portnoy had stated that there was some serious contention about giving JLB publishing credit for songs in which he did not actually contribute, and after 2002 the band decided only members who composed would be allotted a share in the publishing. (Conversely, for example, Red Hot Chili Peppers divide publishing equally, regardless of a member’s contribution, just to maintain a positive vibe and band stability).
Lastly, I will point out that MM called Dream Theater’s self-titled album DT13, a nomenclature that developed around this forum. Pretty cool little nod I think. EDIT and CORRECTION: I think he meant to say DT12, not DT 13!!