<font face="Verdana, Arial, Helvetica, sans-serif" size="2">they'll sell the seat to someone else.</font>
This seems to be the cornerstone of the AC/AP approach to their FF program. Unfortunately, that assumption is almost certainly wrong. People will not buy J when they can't upgrade; unless it's essential they won't buy a revenue ticket if no award seats are available; they won't pay for a higher fare basis ticket just so they can save an hour or two flying standby. It'a astonishing that they continually tout the benefits of AP in theory, but in practice, do very little to recognise those who are loyal to them.
Has anyone tried to work out the rationale for the way in which AP offers benefits? Having SE status really doesn't mean anything at all to those who fly routinely in paid J (other than access to award seats). So the target group has to be those who fly a lot, but not necessarily in J. Some of those will travel full fare and they can take advantage of all of the privileges of high status. But there must be a very large group who fly often, but not always on a Y ticket. These are the people that AC should want to keep as loyal customers, but all of their recent actions seem designed to drive them away. This is particularly the case for those with SuperPrestige status this year. It's hard to understand what the business plan for AP is.
On the main topic of this thread -- I've not had to do it, but I would use points on a business trip if I couldn't justify the cost of a mid-week fare.