When using the following URL: "http://fantasysports.yahooapis.com/fantasy/v2/users;use_login=1/games;game_keys=nfl/teams", and I have created an NFL team but am still waiting to be assigned to a league, usually a public league in this case, the above URL returns errors and does not display information about my other teams.
For instance say we're in week one of real play and I decide to add one more team before th cutoff and just want to be automatically assigned to a public league, I've done this in the past, the API would then fail, using the above URL. Unfortunately using the above URL is the only way I've found to find a users team_key.
If there is a better way to find a team_key, please let me know. Either way, this does not seem like normal behavior and should probably be fixed.