Difference between 1" and 30mm

[Bimmer]

... the 15mm lens can be expected to be about 36% closer to its intended profile than the 11mm lens, at the same level of precision...

I am not an expert on this so while I'm making a statement, it's intended as a question for anyone with expertise to answer.

AFAIK, this is pretty much a non-issue.

People talk about the quality of the "glass" or the "lenses," but for the last couple decades making top quality glass lenses has been easy and cheap.

What separates the good from the bad from the ugly scopes isn't the quality of the lenses themselves as much as the coatings (anti-reflective and anti-fog) and the assembly of the scope (the alignment of the lenses, for example).

So, given that it's not so tough or expensive to start with top quality "glass," it doesn't seem like making good lenses of 11mm diameter vs. 15mm diameter would be much of an issue at all.