It also happens in SIN, but only for smaller a/c like B737 and
A320 as their engine thrust won't overpower the airtug. It
definitely won't happen wif the B777 even in US as they autostart
both engines at the same time and the idle thrust can overpower the
airtug resulting in towbar shear. Has happened in SIN b4.
As i said earlier, any a/c wif thrust reverser can technically back
up on its own, just that it's not recommended by the
manufacturers.