I think it has something to do with the heavy a$$ flywheel. I recently had my clutch and flywheel replaced under warranty for the shudder problem. My clutch is very smooth now but I noticed my rpm's "rev up" a little bit when I shift. And I'm not keeping my foot on the gas, this happens with my foot completely off the gas pedal when depressing the clutch. It is kind of annoying. My theory is the flywheel, but I could be wrong.