I’m a huge proponent of alphabetizing CSS properties inside rules. I feel it helps readability of the rules and minimizes mistakes. The common refrain against this technique is that you should group in-kind properties together. This works for a small subset of properties; however, there are many that don’t fit so nicely with others. How do you order all those other properties? In my mind, it requires too much mental energy to figure out where different properties go. Also, this method opens the door for each developer to interpret it differently. The time to ramp into a project increases dramatically because you have to figure out what the order is. This is more acute when the developer uses no grouping method, instead ordering the properties as they think of them.
Additionally, every developer I’ve ever worked with who doesn’t alphabetize has at some point duplicated a declaration because they didn’t see that it was already in the rule. Additionally, every inspector except IE’s alphabetizes the declarations. They recognize that it’s actually easier to parse alphabetization than declaration type.