If a 2011 grand sport does NOT have it what does it have? I mean is the ride equal to "sport", "tour" or neither?

Neither. If there were a race mode for MRC then it would be between race and sport. Firmer ride. More traction on smooth surfaces. Less traction on bumpy surfaces.

U said "If"...what if there isn't a race mode?

Z51 springs and shocks. Firmer than the 'Sport' mode with the F55 shocks.

There is no race mode. Therefor you just have to guess what that would be like knowing what Z51 was like and what MRC is like. More track capable than any available MRC and less comfortable over potholes than any available MRC.

I almost always agree with you and certainly learn things too, but not on this one. I'd guess you'd have to experience what MRC modes are like vs Z51 to know the difference.

I'm also guessing when the OP is comparing "ride", he means more along the lines of soft vs harsh, which is not a direct function of Tour vs Sport with MRC.

If MRC was less track capable, GM not only wouldn't have it as standard on the ZR1, but they wouldn't have it as part of the Z07 track package on a Z06.

There are different settings for the ZR1 MRC. That's why I started this with "if there were a race mode". Yes, MRC COULD be more track capable but with the factory parts and settings on a base C6 it is not. MRC has been around since 2003 and even some C4s had an option for shocks that had multiple computer controlled damping rates. But when GM wanted to build a Corvette with more track capability (Z06) they always went with "simple" stiff shocks. Why? Because you don't need variable rates on smooth surfaces. You just need real hard fixed rate shocks or no shocks at all. MRC is needed when you want to have better performance on multiple surfaces. You want very hard on small stones and imperfections and very soft when you hit a pothole. But since the car can't predict what's even 1 inch in front of the tire the control has to err on the side of softer.

The Z06 got the highest performance fixed shocks. Z51 was for those who weren't in full track mode but wanted something that handled better than base. F55 was for those who didn't like the firm ride of Z51 but also wanted something better than base. Z06 finally got MRC available in the Z07 package in 2011 but it was dropped as a standard for that package the next year although still available separately. A lot of people wanted the "Ultimate Performance Package" which meant they did not want MRC. ZR1 was the ultimate Corvette and had to satisfy those where cost was no object. It was always to be a very low volume production and there were going to be a lot of frame and suspension changes so they couldn't waste the money developing multiple suspensions. Since the ZR1 was going to cost more than a aftermarket built Z06, it's target market was going to be non-racers with lots of money used to cars with soft rides. Therefor - MRC. And to try to offset some of the development costs, include it in Z07 for Z06s. But they did use different parts and different software to try to make it as track capable as possible and they did a very good job of that as evidenced by the ring times. But to say that MRC is more track capable than Z51 simply because the ZR1 and other very expensive fast cars use it is like saying that having a passenger seat makes the car faster because a Z06 with a passenger seat is faster than a base with the passenger seat removed. Different components in different cars. If MRC was more track capable in the Z06 they wouldn't have removed it from the Z07 package after only one year. Marketing is a large limiting factor in the C6 suspension option capabilities.

MRC is a very viable option on the track if it is a LOT firmer than even the Z51 setup. But what comes out of the factory for MRC is a compromise using MRC to soften the ride, not make it firmer.

I guess we'll have to agree to disagree on this one.
Although I do agree with some of your points, where we differ is our interpretation of how the MRC functions. It appears that you look at it as a device that is simply switchable between soft or firm and I view it as one that is a time reactive variable to complement and assist a lower spring rate. MRC is not about providing a cushy ride for the driver, but about keeping the tires in contact with the pavement. The smoother ride is just a welcomed side effect.

Smoother ride . The fact that the tires stay in contact with the road better on very bumpy surfaces found on the street and not on the track is just a welcomed side effect.