...sometime back I was told to lay the plant in the row longways and they would also grow roots on the buried stem.
Learned something new here!
After reading your post, and a lifetime of planting seedlings just like I would any other seedling, I thought, "What the hay?"
A simple Google search of "How to plant tomato plants" revealed The Experts say to bury the plant all the way so the stem is covered to the leaves!
Reading on, many say it's OK to lay the plant on it's side - it'll quickly grow "up". Problem with this method is hitting the plant with stakes/cages.
Love this place... Like I said, I learn SO MUCH!