Instead of checking for exclusion of Avg,  it would be better to have a separate AggrThpyes3.tdd consisting of the new functions.  The general idea was that AggrTypes1 contains aggr functions that have 1 running workspace variable, AggrType2 contains aggr functions that have 2 running workspace variables.  Since stddev, variance have 3 running workspace variables, why not put them in their own  tdd  file ...