Update:
A fellow regular Moon Rabbit (76561198370444405) sent me this:
"1) Join or rejoin in time for a new pre-round
2) Before joining any team, choose a class via "join_class [Class]"
3) At this point it's already finished, but you can select a team however long after spawning in and roam around the map normally. Can join either blue or red.
This exploit spawns the player in a unique location for every map. On Warebloom r1a it spawns the player right on the cap point. On 2fortdesk it spawns the player some meters directly in front of red team. On dust and military area it spawns the player underground.
Joining Blue does not appear to prevent Red victory when hale is killed
I believe joining Spectator simply suicides your character as if switching teams normally
Once spawned in after (2), your character is on the map and can be killed before joining teams
Can only be done once per joining
I don't know any pattern for which players crash, but it appears to be no more than 4-6 at a time"
After testing this, I can confirm that it does work and that the other occurrences Moon Rabbit mentioned do happen. However, if you join a team before the round starts, you will be automatically put onto Red when the round begins. If you wait until afterwards to join a team, you will not be placed on Red and can play on Blue freely.
Demo File (Bug preformed on vsh_supermario_v2):
https://mega.nz/#!CkAiRASa!qcOtxuwv-4s4I54dcZggXhikU0CNmB5VgR3fIhUdMFM
As a rather amusing side-note, preforming this bug on Minegay spawns you under the map, unable to move, taunt, or otherwise do anything. The situation is similar on Supermario, with the exception that you spawn half-way in the floor on the middle point.
