Those that he is credited on, typically say Degarmo/Tate/Wilton, but very few that say Tate/Wilton or DeGarmo/Wilton. You get the sense that he wasn't often the primary songwriter.
In addition, Wilton had a chance to shine when DeGarmo left. However, this was the band's worst period.
Finally, the fact that most of Operation: Mindcrime II was written without him contributing, suggests he didn't have a ton of ideas. If they were trying to recapture the magic of O:Mc, than who better than one of the guitar players who helped pen it? Yet... he contributed nothing. It's hard to believe he was just hanging out in studio, with all these killer O:Mc like riffs, and they chose to let Slater and Stone write it instead.
Perhaps Michael Wilton is sitting on a pile of great Queensryche riffs, that will harken back to the days of The Warning. I just don't think so.
I'm pretty sure the reason Wilton was always listed last on the songwriting credits is because they were listed in alphabetical order of their last names. There are a few examples where Rockenfield was listed before Tate, as well as Jackson. I'll list some examples of where DeGarmo/Wilton & Tate/Wilton were given writing credit (not to be a dick, but simply as a reference). There are a bunch more songs where credit was given to DeGarmo/Tate/Wilton. I always felt that during the classic period (The EP through Empire), that DeGarmo and Wilton wrote the music and Tate wrote the majority of the lyrics/vocal melodies. If you look at it, DeGarmo probably wrote 60% of the music to Wilton's 40%. DeGarmo always seemed to have a little bit more of a melodic tinge to his riffs/songs, whereas Wilton was more straight ahead metal IMO.
I agree with you that Wilton had the chance to shine once DeGarmo left, but it was obvious even before he left that the bands sound was changing. Was it due to different musical tastes or lack of inspiration? Who knows, but I think its safe to assume that Tate hasn't really been into playing metal/hard rock for sometime now. Does Wilton have the ability to write some tunes that harken back to the glory days? Only time will tell, but I'm happy Todd has gotten the opportunity to shine and that the negative energy that Tate brought to the other members is finally gone. They seem happy, and that's really all that matters. Happy bandmembers usually equals great music and ideas.
Nightrider (DeGarmo/Wilton)
Blinded (DeGarmo/Wilton)
Surgical Strike (DeGarmo/Wilton)
One And Only (DeGarmo/Wilton)
Warning (Tate/Wilton)
Before The Storm (Tate/Wilton)
Child Of Fire (Tate/Wilton)
Walk In The Shadows (Tate/Wilton)
I Dream In Infrared (Tate/Wilton)
Chemical Youth (Tate/Wilton)
Revolution Calling (Tate/Wilton)
Speak (Tate/Wilton)
Spreading The Disease (Tate/Wilton)
The Needle Lies (Tate/Wilton)
Empire (Tate/Wilton)
Resistance (Tate/Wilton)
