If I live to be a 100, I will never purposefully stunt a tomato plant.
This "northern Gardner" says if you need to slow the growth down, they were planted too early.
For my purposes, I plant my seeds and do everything I can to maximise as rapid and vigorous growth as I can so that the plants "hit the ground running" right from the get-go with as large as I can manage and already blooming plants ready for the garden at the right time (well after danger of frost) . Having a greenhouse or the dedication to bring plants in and out and the space to pot up to litre + pots is required for my method but I always had ripe tomatoes in the middle of july in a Zone 3 outdoor garden. I have never pinched a blossom in my gardening life either.
I believe that Tomato seedlings want to grow fast and they do better if you let them and help them. I think more focus should be on sowing at the right time and not sowing more than can be managed with good light, watering, fertilizer and warmth. In particular in a short season garden I observe gardeners struggling using the same technique and timing as our southerly neighbors and it is causing more problems than it solves I think.
My Northerly perspective for what it's worth
KarenO who doesn't believe in "cold treatment", not fertilizing seedlings , blossom pinching, small seedling cups, DE, or under watering of tomato seedlings. I am Not trying to start an argument but there is more than one way to do things and if gardeners are having trouble, try something different next year .