a few potentially significant impovements to strict calculations.  1. Do not recurse into subtree if conflicting triplet has been winnowed 2. Declare conflict without recursion if a triplet on the same taxon set as the conflicting triplet exists 3. Precompute components at root, build upon that by adding conflicting triplets during the root calculations. These amount to at least 20% speed increases on some datasets, possibly much more in other situations.