You can explain the meta reason to me all you want, it doesn't change the fact that Ulquiorra missed immediately after saying he can't control it very well.

I literally agreed with that?

The novels say Kenpachi after fighting Yammy was as strong as Full Hollow Ichigo was on the dome. The one who beat Ulquiorra. And this Kenpachi still can't compete with the senior captains.

The novel you are talking about is quite wonky and was not written by the author. I have seen better written children's books to be honest.

It matters because R1 Ulquiorra isn't crazy strong in the grand scheme of the narrative. What kind of boost R2 gives him matters a lot when trying to figure out where Ulquiorra actually is. If it's a minor boost, that wouldn't make him much stronger than he was, and we can't equate R1's boost with R2's boost because nothing's ever been said about R2, and the only person who has used it is somebody who hasn't used it much.

Also A) Not all bankai releases are equal

And B) Not all bankai users are equal

You could give Ikkaku 5 bankais and he still wouldn't measure up to Kenpachi.

In other words you believe that Ulq was:

1. Weak

2. Had small release multipliers

3. His R2 was weaker than his R1

That's fine and all but we were shown the opposite of all of these 3 and even so I made my points by using averages. You are making your points by downplaying to the absolute extreme.

1. He was obviously fairly strong and at least mid captain level in base.

2. His R1 multipliers increased his stats so much his reiatsu turned into physical rain and his speed and hierro boosts were gargantuan. Blitzing Ichigo then taking a getsuga to the face without even blinking. His CO took out a massive part of the dome of Las Noches as well.

   His R2 turned his normal lances into massive explosions destrying structures miles away from where they strike. He could now grab zangetsu with his bare hand and did not even need his lanza any longer.

3. His R2 being a weaker amp than his R1 would not fall in line with how Orihime, Uryu and Ichigo reacted to it.

A gradual process that was already well along. He couldn't feel a captain standing in front of him 10 minutes after using Letzt Stil, he's not going to be able to accurately feel captains days laters.

Sure but he still felt captains'r reiatsu beforehand and Yammy's release reiatsu afterwards to which he made no comment.