Talk:Tips and Tricks/@comment-187.189.173.144-20140814174124/@comment-137.207.75.220-20140912003211

Though putting the above into better math, single reinvocation will be superior if rerolling the Bs results in a greater than 10% decrease in the number of Bs (poorly worded probably)

or simply:

% occurance of B > sqrt(10%)

% occurance of B > 31.6%

So if you think you roll Bs more than 31.6% of the time... single reinvocation is better. This number shrinks if you reroll As you don't like. And since I'm pretty darn sure that the occurence rate for Bs is higher than 31.% I'm always working with single reinvokes.