[wireties]

We used mecanums for 4 years and my observations jive with Ether's statements. There is no limit to max fwd velocity related to the angle of the rollers - no question. Our designs were square with even weight distribution and encoder feedback. The forward speed was very close to the calculations (same used for tank). It is very different going sideways of course and it might slip quicker if you accelerate too quickly. We pushed kit bots around, went over bumps, got up on the bridge etc. The 70.7% number is tossed around all the time but it is not true (going straight forward), if mounted properly the rollers do not rotate all the time.