What is the letter "N" in ASL?

Double-N:
In regard to double-N (also known as "NN")
Try (on a full-size desktop browser) going to the 1:12 mark of this video:
https://youtu.be/HCEdGSptw4Y?t=72
and slow your speed down to 25% and note how Anne is being spelled. Note the
almost imperceptible reformation.
Then go to this video and note at the 4:18 mark the very pronounced re-formed N
approach is used to create a double N:
https://youtu.be/xNm38yv_uns?t=256
Yet at the 1:16 mark of this video we definitely see the slide version of NN
being done by a very skilled signer.
https://youtu.be/RksYR3XiDRg?t=75
What is my point?
Both (sliding and reforming) are most definitely right ways to do double-Ns.
However in the literature and from gurus at the front of classrooms we are often
told that one or the other way is correct.
I encourage you to nod politely, do it the way you need to in order to get
whatever grade the guru is handing out -- then move on with life -- comforted in
knowing that you are okay either way in the Deaf community -- unless you run
into a guru who has taught from prescriptive literature for years and has
fossilized on what they mistakenly believe to be the "only right way" to do it.
Notes: