Tomato pruning

Hi all,
I just found out about this video about pruning tomatoes which I thought would be interesting for all who don't know about these things (such as I)  It is from an interesting web site of a local (CT) woman.

I have six blueberry bushes that I bought a few years ago that are just now starting to look bushy. Three of them, however, have never flowered. I thought blueberry bushes would pollinate themselves since the other three are obviously female and produce fruit. I'm not sure what to do with these non-producing bushes now...?