I agree that widebodies are better all things equal. Maybe this is cherry picking, but I checked a couple random dates for DL-One vs Mint for trips on the same days and JB was well under half the cost. They don't have to strike revenue gold and out generate existing revenue; all they have to do is reduce yields and dump capacity enough to survive and they win simply by taking existing marketshare. Ignoring them out of an overconfidence about widebodies is a mistake. If they are poaching any premium pax whatsoever (and they clearly are) they are draining legacy airline's most valueable source of revenue and profits. Soon it will be tens of thousands of lay flat seats a year and growing. These aren't $49 cruise ship connection super savers; this is a direct attack on the crown jewels of revenue generation and ignoring it because its "just one flight" or "just two flights" etc will prove to be a complete blunder. This is a serious challenge that will grow significantly going forward. Airlines will either spend the money to deal with it now or they will inherit a far more costly battle long term.