Strange growth from Cotyledon with mainlined plant:

So I have been growing for about a year and a half now but I have been around growers for a number of years, I am havinga strange event happen with 11 of my 19 plants at the moment and I am curious to see the results but am not sure if it is a good idea. We grow inside in a 8 by 4 tent with 2 600's and a 1000 watt hps/mh, mainline after 6th node to only the 3rd then rinse and repeat until desired number of tops. However unlike my previous few grows, after topping these plants (cookies kush) the tops didn't grow as fast but instead either the Cotyledon leaves fell off and a new node appeared or they were almost pushed up and a new node formed under it. Never seen that from the Cotyledon set of leaves before and it was hard to find a post with anything about it really. My main focus is with the mainlining technique, even though it seems cool and odd, should I just chop it off like the other nodes. My last grow we did the 2nd and 3rd node to try to save time with using techinques taken from the clone manlining guide to stunt the top growth while the lower growth caught up. It was a decent success but the colas alas were not as big on the lower branches, the saved time meant starting a new grow sooner but 10 days is not that big a deal atm. Just curious what I should do.

This is odd and if it were me I'd cut them off as their obviously not going to yield from there. I'd guess that when you cut the branches above it signaled something that told the the plant to throw out a node… I don't get all the plant science.. no one does..

It's totally normal and there is nothing to be worry about. Cut them off!

Strange... But... Me also i have some strange behavior on my newly mainlined plant, a Ketama feminized seed from World Of Seeds. One of my first two grow tips
to be bended down to provide the first 2 colas (i want to have 8 colas so i have two more tops to do), is shorter than the other part! Let me show u what i mean...




The grow tip on the bottom is the shorter one of the two... Notice the fan leaf on the left that seems like to have a little bit of a strange mutation... I should have probably cut at the 4th
node and not on the 3rd one because that grow tips were perfectly simmetrical...

Do you think guys i still have hope to develop a nice looking plant? It's the first time i try to mainline weed (i heard of this technique only a month ago...)