Tumbler Tomatoes Question

I have never had much success with tumbler tomatoes but I am trying again this year. My question is,  Should you pinch out the growing tip to encourage the side shoots?

I grow two varieties, Tumbler and Yellow tumbler, large pot stood on top of a similar pot which is placed upside down.

They do go a bit wild, but the crop has always been fantastic and are early, before the 'main' vines 

I always have two plants per 14" basket and three plants to a 18" manger. I start them off in the greenhouse then move them to a cold frame before planting them out.