An interesting development. I have previously used these tickets and found them very convenient.
The ability to book on line is an improvement and I guess they have to have these conditions to avoid invalid passengers booking them. Booking on line also saves the various booking fees that airlines charge to book over the phone.
I wonder if it would be easier to follow the JR Pass conditions where they ensure you are there on a tourist visa? They they only have to look at your passport.
That would be great. There are people Japanese residents with foreign passports taking advantage of this because of the way overseas JAL offices enforce it. I hope JAL will follow JR and check the entry stamp. But then Yokoso is designed for people living overseas so Japan passport holders are actually eligible for these tickets (I have confirmation from JAL about this). So checking the visa stamp won't work unless they change the rules such that only people with temporary visa stamps (e.g. tourist, short term business visa, etc) are eligible