2001 D Lincoln Cent Small Date Variety?

Well first off all of the 2001-2003 have a larger date than other years. If the devices are smaller (Or the same as normal sized other years, the the die was probably polished on one or more dies and the devices would appear smaller on some of the cents that year.

Note the above simulation:
when the fields on the die (the outside part of the die) are polished down, the fields are reduced in height. This reduction make the size of the devices smaller. this this why there is a difference in size. But they all came from the same chain of command and the die was normal, until the die polishing. So this is a die event, not a die variety. If they had two different die sizes that year, all would know about it. But on the coins you are finding alike were probably all struck the same altered die. (Just a die event)

CoopHome: Why are some devices smaller than normal? die polishing will alter devices. sometimes isolated device can be even removed on the shallow devices of the die. thus the missing letters/initial/feet/peg leg and other die events that really are just a die polishing issue, not a different design. The dies were normal until they were altered by polishing. (again, a die event)

I agree with john1

I think you may be on to something here. In your last image (even though it is blurry - and that may be the reason, but) but the zero's are rounder on the bottom coin and the 2 is a different shape.
Or I could be way off base here.

Here is a better pic. I also notice that the zeros are different sizes. On the larger date the larger zero is next to the 2 and the smaller date, the larger zero is next to the 1

Ok now with better images, the coins all look pretty much the same...