  We show that the left-greedy algorithm is a better algorithm than the
right-greedy algorithm for sorting permutations using t stacks in series when
t>1. We also supply a method for constructing some permutations that can be
sorted by t stacks in series and from this get a lower bound on the number of
permutations of length n that are sortable by t stacks in series. Finally we
show that the left-greedy algorithm is neither optimal nor defines a closed
class of permutations for t>2.
