Nick The Beard

I put 29x2.0 on mine no problem but wouldn't try anything fatter. The clearance with the rear tire is really tight. Also remember that some manufacturers might measure their tires a little diff and diff rim widths and tire pressures can affect actual tire size. Many Cross-check owners report fitting up to the same size (29x2, 700x50, 622x50, etc... same thing)

As far as why, I don't know why the OP wants to but I did it because I like to take my bike off road from time to time. It turns out that these tires don't have any more rolling resistance than the 28mm slicks I had on before so I'm leaving them on for city use also since they add a nice bit of cushion over bumps and stuff. Also, it looks cool as F.