20 blogs isn't enough to matter or hurt anything and linking them all together isn't going to hurt anything. There is no harm at all in linking your own sites together as long as you are not doing it too fast - i.e. linking 1000 blogs to a target site in one day. If they are site-wide links, you might want to do 10 a day or something.. but its not going to hurt anything.
People come up with all these crazy names and diagrams for link strategies which all do only one thing... put distance between the money site and the inbound links. Doesn't matter what you call it.. "butterfly" "fruitfly" or "moth" or whatever. Doesn't matter a whole lot how you do it. It doesn't need to be complicated and It's all the same thing... nothing special and it's pointless unless you are doing it on a large scale or continually building for the long term as the link values are going to be negligible as it is... much more so when linked to intermediary sites, then to the money site.
