These are my discoveries
It's not straight forward using taxonomy as a node reference mechanism.  Taxonomy is arbitrary.  Nodes are not.  When we're tagging content as "awesome" or "useful", then taxonomy is great.  But, if we can to tie a single node to a series of other nodes, then what we need is the node ID of those other nodes in an enum on this node.  That's what node reference does.  Node reference was eliminated from core in D7.  Fortunately, it lives on in a module but Relation will replace it and that module didn't make sense to me.