I will dance like a monkey IF I think that will help kids learn and be proud of it. There is tremendous satisfaction when you win. I accept that might mean you win with less than 10% (so its the same everywhere) but I will take that 10% and have tremendous job satisfaction.

But as for illegal visas or unqualified documents yes you are giving a very very fair warning:

employers actually prefer employees who can't secure legal documents--because said
employees cannot appeal to SAFEA when the employers don't pay them or otherwise honor
their contract (it is the rare Mainlander that actually believes in honoring business
agreements). Believe me, if you are working for a training center in China on an illegal
visa...they will have you over a barrel in a foreign land. Don't expect them to not
screw you over--

They will even enjoy hearing about a fiance and plans to marry a local girl because they know that means the foreigner has huge personal obligations, motivations to stay no matter what happens. This means the foreigner is going to soon have more financial needs and obligations and that means this foreigner can be used, squeezed, scammed and will have to take it.

So the best advice for the Australian is to always remember that no matter what happens he is financially stable, has his own money, remind them he has a paid ticket home (especially that) do not indicate any needs or obligations to stay in China and act like he doesn't need to be there but just wants to be there.