Well, no because in practice the exorbitantly priced seats are actually just higher fare classes; V fares will still be just as cheap as they are usually. Most times, when a friend tells me the seats are really expensive, it's usually because there are only Y/B fares left, so of course it's expensive.

Well at least it works on CX because we can book cheaper fares (all the way down to V fares). I have seat guarantees on CA as well, but I can only use it to book Y fares which depending on routes can get pretty nasty (for most domestic routes, it's okay).