You said — “Which causes me to ask two questions: First, in what way does their behavior differ from OPEC’s? Second, what good would it have done to have additional refinery capacity on line?”
Well, there’s a big difference form OPEC. The refineries are not an organization that requires their individual members to meet certain quotas (either up or down). They are not organized to collude with one another.
Now..., to have one look at another (refinery) and see what they are doing and to match it (pricewise or cutting back on production) is not illegal for them to do. In fact, I don’t think it’s illegal for them to shut down half of their capacity, if they wanted to, or shut it all down. Of course, they wouldn’t shut it all down, unless it was necessary, because they do want to “make money” from their facility... LOL...
But, there’s nothing to tell them, legally, what quantities they must put out. If one thinks that they should meet certain quantities for output according to whatever conditions one sees in the marketplace (in other words, increase production to prevent prices from climbing too high) — then perhaps what you really want is a government-driven department that dictates to the refineries what output them should meet at any particular time, according to what the government thinks is needed.
If not that, then, since they are a company in which (a capitalistic system), making the most money possible for a company is supposed to “work out” in the end (in that if they price it too high, then others will come in and take away marketshare, or if they price it too low, they will go out of business). So, if the government stays out of their production quantities and their pricing mechanisms, then those refineries can price it at whatever price they want, and can continue to sell it at (given that people will continue to buy it, no matter what...).
If that is true, we ought to see some refiners ramping up to 100% capacity to take market share away from those who are cutting back. And if I saw that happening, I would concede your point. Unfortunately I do not know where to easily access that information.