Let's look at this in a more detailed manner. Two things that people seem to look down upon are having, say, 10 kyu ranks, as well as double promotions.
Is having 10 kyu ranks excessive? Maybe so. After all, in my previous post, I did mention that there are still some styles that only use a limited number of kyu ranks, such as going directly from white to green to brown, and then to black. Many of these styles are quite successful, and produce fine karate-ka.
However, there are honestly some times where having those 10 kyu ranks are a good thing. Some children might be slower learners than others, yet would not really benefit from being held back at white belt. Some simply can't take in that much information at one time, and having those 10 kyu ranks gives you the flexibility to give them something. I've had a couple of children with learning disabilities turn out to be decent karate-ka, even if they did take a significantly longer period of time than their peers did.
At the same time, double promotions (or even, yes, triple promotions in the case of a white belt) can render the need for 10 kyu ranks all but unnecessary in the cases where a student is dedicated to training, and a capable talent. The way I see it, just because a system does have 10 kyu ranks, does not necessarily mean that all 10 must be employed for every student there. Different strokes for different folks, naturally, and some are going to be better than others. The way I see it, if someone has demonstrated the knowledge and proficiency to get a higher rank than what he was supposed to test for, then I see no reason why he shouldn't get the higher rank.
Where I DO disapprove of the 10 kyu system, is where the chief instructor forces everyone to go through all 10 kyu ranks, regardless of how well they have done. In my opinion, there's no good to hold back capable students if the need is simply not there.
I will also certainly disapprove of the use of double promotions when they are not merited.