i think that you are right vance.. they are not stretching... they DID stretch already.. that is why they have a couple inches above the soil for the first set of leaves.. and a 1/4 inch is stretch but i think that it is in the OK margin.. i allow/encourage a bit of stretch before the first set so that when i transplant i have some room to work with.. ya know?
unless you are pumping some serious lumens onto the babies then they will stretch a bit between nodes and that is ok unless you have a 1000w MH on em then something is VERY wrong.
have fun and if i am wrong someone will step in but i am fairly sure im right...
-J