Wow, So long a post, my patience duly rewarded.
I will try one thing at a time.
That is an excellent idea, to start with.
It would be an equally good idea if you follow up every aspect of every answer fully. Do yourself the favour to read carefully what others have written; none of it is casual or accidental.
For instance, the posted link also contains a description of how the chakram was used. Possibly you have missed that.
Secondly, the finger-whirling technique can be used only with very small chakrams, although this was the traditional way in which Sri Krishna used his Sudarshan Chakra; the way he carries it, constantly whirling on his forefinger, says it all.
However, this is grossly impractical; the quoit technique - frisbee, as you have called it, and as it is indeed called in modern times, although war-quoit is what it was and it was like a quoit that it was used - is actually the correct one for larger sizes.
The reason is that smaller quoits/ chakram are not very effective, taking too long to reach launch velocity around the finger (try it for yourself; I have).
Secondly, a small quoit does not travel far. So in close combat, if you see someone pluck the chakram out and start twirling it about his finger, you don't just sit there and wait to be sliced open, you put your shield up, if bearing a shield, or take alternative (rather urgent) action, either offensive or defensive. It is at ranges outside sword or spear range but not much further that a small finger-launched quoit might be effective, largely because of surprise.
Only the very smallest are launched like that. The larger ones, the ones, for instance, that the soldiers wear as part of their headgear, even now, in the Sikh Regiment, are thrown backhanded, from the right hand from a tucked away position deep towards the left outward at the enemy.
This is not the wrong technique, as you have said; it is the correct one for the larger sizes. It also allows a slightly longer range, awkwardly out of the reach of hand-weaponry, and is difficult to intercept if otherwise engaged in close combat with someone else, the ideal battle situation when it is to be used.
In other words, it is best used against an enemy swordsman or pikeman or spearman already fully engaged a slight distance away, and unable to pay full attention to you wrestling with your headgear to pluck a quoit out!
You are possibly influenced by the mythical method, the method used by Krishna in launching his Sudarshan Chakra, which as it happens is a practicable method, save for the fact that such a technique would not carry long distances (mythical references and mythical distances may be left in the myths - let the myth bury the myth).
For close quarters combat, it is a complete fiasco. I would strongly not recommend to anyone a pause in close quarters combat and a retirement to release a chakram, place it on a suitable forefinger, and then start twirling it. What the opponent or any random passing swordsman or spear-holder would do with this lengthy interval doesn't bear thinking about. So if you find yourself in a sword-fight or a knife-fight, don't bother to pause to unlimber your quoit; if you do that, you are history.
Sikhs know how to use Chakram, War Quoits (Not to be confused with Sudarshana Chakra or Quoit of Zena).
As a matter of fact, the technique that you have described as 'correct', the finger-launched technique, is exactly that used for the Sudarshan. So it is a little confused, more than a little confused, to say that that the Sikh Chakram is not to be confused with the Sudarshana.
I remember seeing a video on youtube in which a young Akali warrior shows some sword forms and then threw some chakram, first small about 4 inches diameter, by whirling very quickly chakram around index finger, hand at the level little above head, and with a snap hurl it towards target.
A correct technique indeed.
Only for very small chakrams, but generally wrong for larger sizes, for the reasons mentioned above.
He, Akali, then threw larger chakram (about the size shown in your posted link) like a Frisbee, hand wrapped around outer edge, pulled back under other armpit, released imparting a spin with the power of arm.
A Wrong technique, i am afraid.
And how did you come to that magisterial conclusion? What I have described, I have described on the basis of the practices of the Buddha Dal Nihangs, who keep up these practices to this day. And they demonstrated this precise combination of technique, with the use of the finger-launched technique not ruled out for smaller quoits.
In short, there are two techniques for the two size-ranges, and it is incorrect to describe one or the other as canonical.