I have never heard a reader of technical documentation say, "You know what what I like about the Big Company's documentation? They consistently bold face programming elements and keywords but never parameters. It's like they read my mind about how I want to see parameters: Consistently Italicized."

Can you imagine a pharmaceutical company producing questionable pills? They are tainted but at least they are consistent?

I have written and read a lot of pages of documentation in my 20 year career. I would say that the most praised documentation, the most appreciated documentation, is any documentation that helps the reader. It could be a ransom note or scrawled on a wet paper towell but if it said, "to defuse tHe bomb cut the red wire first. Then: cut the ;blue wire." No one would say a word about consistency.

I'm not saying that technical communicators should trash all style guides and start re-inventing the wheel. Consistency is probably good, but, and this is the kicker, it should be a by-product of producing excellent and useful content – when that is what is needed or required by one's employer.

You can take crappy documentation and make it consistent. It still isn't good. It has to be good, first, or no one cares. I don't ever want to see "consistent" as a goal of a content project. Consistency is like a principle or an attribute of good documentation. Even then, you have to wary of a trap because it could simply be a common element. For example, you could reach a false conclusion and say, "of all the documents on our web site – the most frequent download is the one where we used Tahoma font. Let's go back and retrofit all of our documents with Tahoma."

An "API" might have hundreds of classes and thousands of methods. You can find tools to list them all and create skeletons that you might later flesh-out. Easy enough. And most likely, they'll be fairly consistent. You can probably create some automation around consistency. And if you can't, then the underlying content probably has more problems than being just inconsistent. Now what?