It creaked and groaned
relatively more than the CAAD 9. All bikes do to some extent.
I can tell the difference in the suppleness that's for sure.
Anything else you want to challenge me on?
It wasn't personal. I was just pointing out that whatever we think, and we all do this, the 'feel' we get from a bike is mostly down to a combination of size, geometry, contact points and components - handlebars flex more than most things, wheels and tyres are the most important thing for the comfort of the ride - and even psychological things like frame colour! It isn't really the imperceptible differences in frame materials and superficial design 'innovations' from one model to the next.
And as for the creaking and groaning, I didn't doubt that your
bike creaked and groaned, I did doubt that your
frame creaked and groaned. The former is normal and a lot of it can be remedied, the latter might indicate a problem. Just trying to help out...
The late great Sheldon Brown has a lot more on frame materials and their effects:
http://www.sheldonbrown.com/frame-materials.html