Your first quote is out of context. They also say smaller teams prefer cluster related properties together. They don't talk about what's best and what's not. It is [here](https://github.com/necolas/idiomatic-css#declaration-order).

Here are a couple of places where people use cluster related order

[CSS Wizardy](https://github.com/csswizardry/CSS-Guidelines#anatomy-of-rulesets)
[CSS Tricjs](http://css-tricks.com/poll-results-how-do-you-order-your-css-properties/)

These guys are well known in the css world. Here are some more.

[Wordpress](http://make.wordpress.org/core/handbook/coding-standards/css/#property-ordering)
[Adam Oliver](https://github.com/adamoliver/css-guidelines#coding-style)

From what I've read the only advantage with alphabetical order is that everyone knows it's right just by looking at it's and easier in bigger teams. 

It doesn't apply to us I think. I like to see related properties together like: **width** and **height**.

Understanding the order is part of really learning the language, or at least it should be, css should not be brute force.

If it works doesn't mean it is right.