Some people even strip off the lower leaves and stem and plant them deeper yet.
Yeah, I do that. I've also had good results by following the advice of the ladies at the farmers market who I buy my heirloom tomato seedlings from: dig a hole about a foot away from where the plant will be; stick a used, empty 1 gallon plastic plant pot in the hole so that just the top rim of the pot is above grade; water the plant by filling the pot with your hose, wait for the water to drain through the holes in the bottom of the pot, and repeat once or twice. This gets the water down where it's needed, encourages the roots to grow nice and deep, and minimizes soil being splashed up onto the leaves, which is apparently how a lot of the diseases that can affect tomatoes are transmitted. You also end up using a lot less water than you do if you just go out and hose down the ground.
I'm trying something different this year: no tomato plants in the ground (none of the available small patches of dirt where I live have day-long exposure to the sun); I've built two
EarthTainer self-watering planters and have them sitting on my relatively sunny patio. I have a Brandywine and a Black Krim in one and a St. Pierre and a Cuor di Bue in the other. I had the seedlings sitting around for longer than would have been optimal, while I chased down all the stuff for the planters, but they're all set now and looking good so far. Also have some peppers planted in a smaller, similar planter.