Number of trusses?

This raises an interesting question, how much space do you give between plants?

The reason I pinch out is I find it easier to see what the plant is upto. They are always growing new armpits, sprouting off the end of trusses. My plants are about a foot apart and they will cross over in the greenhouse, so I cut back the branches by half. These often sprout New growth as well.

You could say I do extreme topiary on my tomatoes, in part because I want all effort concentrated on the fruit and not growing extra limbs. It gets harder and harder the taller the plant gets.

I’m doubtful of your ox heart JJB, one limb will be weaker, and you will have to support the fruit more as the limb not growing vertically could snap under the weight of the fruit. I’d be interested to know if you get more fruit or smaller fruit as a result?

When you say cut branches by half, do you mean leaves or growing points?   My toms are grown vertically and arm pitted usually single stemmed, except for two this year which grew unintentional armpits that I missed, both plants are large fruited unfortunately,  oxheat cour di bue, and black russian.   The second unintentional stem is also supported by tying to  a vertical cane.  The height is restricted by the GH roof.  The individual plants are zigzagged about 2' apart giving 5 plants down a 8' border.  Even at this spacing the GH gets like the Amazon jungle and I have to remove leaves just go see what's what.   On a tom growing website they explained the science behind the strategic pruning of certain leaves and their relationship to the ripening fruit which I found very interesting.  I will tend the oxheart and black russian the same as I do all others and see what happens.  Oh yes, there is a third with a second armpit overgrowth Sweet Cassaday which is all rather weedy so I chopped the long armpit after the first truss and told it to stop sulking.