Reading the article the biggest thing that hit me is that the two versions of the union paragraph are not equivalent at all.
The first one says that the labor movement was not founded by heros. It insinuates that anyone who claims otherwise must despise current labor unions by contrast. And it leaves open the possibility that you're setting the reader up for a sudden about face where you come up with some non-obvious reasoning for why labor unions were founded by heros after all.
The second eulogizes the heros who founded labor unions. Then makes it clear that there is no reason to think that current union leaders would be capable of less if asked. And concludes that the shrinking of unions must be due to external circumstances.
With that in mind I can draw up version 3 that says what version 2 does but not at length.
"Why are labor unions shrinking today? Some say that we have lesser leaders today. Admittedly today's leaders do not regularly face hired thugs, etc like their predecessors did. But there is no reason to believe that they would be any less capable of heroism at need. The cause must be external."
I made the same major points as #3, without causing offense, with fewer words than your short version. The secret is to avoid offense by figuring out what could be offensive and not saying it, rather than figuring out what could be offensive and elaborating on how you're not trying to offend.
You know, as I was cutting out the stuff about Arrington, I was thinking to myself, what is the second biggest bicycle shed? What controversial but peripheral issue are people going to seize on now? Labor unions, probably.
Ugh. After spending so much of yesterday arguing about whether people's dislike of Arrington was due purely to their high standards for journalistic integrity, or whether (this being the whole point of a disarming manner) they were also influenced by his manner, I just can't face the prospect of spending any of today arguing about labor unions.
I did not say that the labor movement wasn't founded by heroes, but that is the last I have to say about it.
I don't think btilly is bike-shedding here. He's not arguing about whether you're right or wrong about labor unions. He's talking about whether or not your (new) first example actually supports your thesis (part of your thesis being that you have to choose between inoffensive writing and clear/concise writing).
You give two versions of the "labor union" paragraph. One of them does not say whether early union leaders were heroes or not (but might carelessly be read to imply that they aren't). The second states that they definitely were.
The second version is less offensive to people with pro-union biases. But it is more offensive to people with anti-union biases. If you wanted to avoid offending a particular person or group, your rewriting approach would work. But to avoid offending a diverse population you should instead remove any claims (express or implied) about unrelated controversial topics, or simply choose less divisive topics for your examples.
As mbrubeck said, I am not arguing about labor unions. I am arguing that your second paragraph does not offend labor union supporters because it says something different, and not because it says things at more length. Which contradicts your thesis that conciseness and politeness are at odds here.
To illustrate how different the two paragraphs are, the first paragraph could easily be a lead-in to an essay that argues that an environment that requires personal heroics from leaders drives away the dreck that are mismanaging labor unions today. This would be an example of the "sudden about face" that I referred to in my earlier response. The second paragraph could not be used to start that essay. Nor could the concise third version that I offered. The fact that one naturally leads to an argument that the other two do not proves their inequivalence.
That said, you're right that I was wrong to bluntly state that your first version said that labor unions weren't founded by heros. It says that anyone who claims that has difficult problem to explain, which leads people to conclude that they were not founded by heros. But doesn't state that conclusion. And, as I noted in my initial response, room has been left for solving the difficult problem instead.
The first one says that the labor movement was not founded by heros. It insinuates that anyone who claims otherwise must despise current labor unions by contrast. And it leaves open the possibility that you're setting the reader up for a sudden about face where you come up with some non-obvious reasoning for why labor unions were founded by heros after all.
The second eulogizes the heros who founded labor unions. Then makes it clear that there is no reason to think that current union leaders would be capable of less if asked. And concludes that the shrinking of unions must be due to external circumstances.
With that in mind I can draw up version 3 that says what version 2 does but not at length.
"Why are labor unions shrinking today? Some say that we have lesser leaders today. Admittedly today's leaders do not regularly face hired thugs, etc like their predecessors did. But there is no reason to believe that they would be any less capable of heroism at need. The cause must be external."
I made the same major points as #3, without causing offense, with fewer words than your short version. The secret is to avoid offense by figuring out what could be offensive and not saying it, rather than figuring out what could be offensive and elaborating on how you're not trying to offend.