Statistics for Six Sigma

You can do just fine. Relative to statistics you need only understand what they can do for you relative to analyzing data. There are software tools available to do the calculations.
Just pay close attention to the theory behind the use of statistics.

I reccomend taking at least one semester of statistics if you want to be a good black belt.  Neither a lack of training in statistics, nor a six weeks seminar in six sigma will make you a “good” black belt.  It not a matter of running Minitab or calculating a hand full of formulas, you have to understand the theoretical bases of the statistics and choose the right formulas and evaluate the computed statistics correctly.  Be cautious with Minitab…it gives you what you ask for.  If you ask it for the wrong thing or don’t know how to interpret the results, Minitab won’t tell you so.