Question about Hakkeshou Kaiten.

[King]

Hakkeshou Kaiten (Eight Trigrams Palms Revolving Heaven)
Rank: B
Range: Close (0m ~ 5m)
Type: Defensive
Handseals: -
Chakra Consumption: Mid: Mid sustain
Like many of the Jyuuken techniques, Kaiten is a special technique passed down through the main family line. Kaiten takes advantage of several of the unique abilities of the Byakugan eye, including an almost complete 360 degree view of their surroundings, so that the member to see all angles around them. As such, if an attack is near, the clan member will release a large of amount of chakra from their tenketsu and, simultaneous to the release, begins to spin like a top, creating a whirling vortex that can nullify almost any attack.

Note: During this technique a Hyuuga produces enough gale-force and chakra to completely resist any attack B-Rank or below.
Successive attacks of B-Rank (three or more) will break the Hyuuga's stance, resulting in the ending of the technique and anything above it's rank will break through. While spinning, the Hyuuga’s vision is severely hampered and blurred (much like a normal person’s), limiting their awareness of what is transpiring outside of the sphere. It should be noted it takes a moment for the Hyuuga to spin-down.

There was a little bit of a debate concerning this technique and its applications, due to the inconsistent nature of the Naruto series. In these two links (1 & 2), Neji demonstrates the Hakkeshou Kaiten as I've always perceived. He is unobstructed and begins to rotate prior to being struck by anything, and the defense activates and protects him (I'm not even going to talk about how he just perfectly started spinning while in mid-air. >_> )

However, in this clip during his fight against Naruto in the Chuunin Exams, Neji is stationary and emits a shield of chakra that protects nothing more than his face. He stands there for several seconds and then wills his chakra to begin spinning, only then following in pursuit after another handful of moments have passed. Being as how this is the only time that has ever happened, I assumed it fell under the "Itachi clause" and would be ruled an outlier and thus unapplicable.

So, the question I'm asking: can a Hyuuga perform the Kaiten after they've been obstructed? Basically, if something is preventing them from spinning (say if someone is holding them down or altering their balance) can they still just yolo and perform the technique? Or is it more of a preventive measure and they go, "Hey, I need to start spinning before I'm knee-deep in shit" like it is predominately demonstrated in the series?

PS: The situation was already resolved but I would like to know for future reference.

[Comatose]

I can see how this can be confusing and it is a good example of why the "Itachi Clause" exists in the first place. Due to how the technique is written, the notion of balance, and a tiny bit of logic (steering away from the Naruto Chuunin Exam example) to use Kaiten you need to be at least able to spin. If something significant obstructs the spin in any way (being held, a wall, column, etc) then you can't begin Kaiten and you cannot use it to block techniques. There may come a time where this is more complicated than a simple can or can't fail state, but this is how it works fundamentally.