I yesterday played 2HG with a friend (and suprisingly, the matchmaking worked). He used a BW Enchantment deck and at some point played Gilt-Leaf Winnower and used Nimbus Wings on it.

Each opponent had one flying creature, one a Pilgrim's Eye, the other a Razorfoot Griffin. The first head apparently wanted to double block the Winnower while the other did not, so the Pilgrim's Eye just sat there trying to block the Winnower while the timer slowly grinded down. At some point I guess the second head got annoyed and blocked it too, at which point the first head removed his flyer from the blockers. As the time ran out, the Winnower was only blocked by the Griffin and it stayed that way, without removing the illegal blocks.

A turn later, the first head tried the same spiel, but was foiled as when the time ran out, the Pilgrim's Eye was removed as blocker and the Winnower went through as he should.