Huh. I'm looking at the companion coupons text again, and they've actually relaxed the restrictions. They're more usable now than they used to be.
They're not very good in coach class because the Saver fare is typically so much cheaper; Value + Companion may be cheaper than 2 saver fares, but often by only a few dollars. If saver fares are not available, then it is quite good. If you need a flexible fare, it saves a lot (but if you need a flexible fare, business class is cheaper). But it used to be, companion coupons were very hard to use outside coach, which was the problem.
However, it looks like now you can use it for:
- Acela Business Class (I think this rarely has saver fares?)
- Business Class (provides a discount equal to the coach fare on the second business class ticket) -- I think you could always do this, and that's how I used them, but it was tricky to arrange and required a phone call. Checking a random Syracuse-Boston trip, the "Value" (base) fare is $52 and business class is $67, so that's worth about $52.
- Sleepers (puts a second person in your sleeper for no extra charge) -- I believe this is new, and now I'll be using that routinely. Again, it ends up being worth the value of one "Value" fare coach ticket, which may be more like $84 for, for example, SYR->CHI.
The increased flexibility for using them on business class and sleepers makes them a lot more useful. Increases the value of Select Plus status (which gives 2) and if used on a sleeper on a longer trip, is probably worth more than the annual fee on the credit card (which gives 1).