In the effort of recording online challenge events I stumbled upon some differences in the MTGO tiebreak system and the current MTR recommendations that I felt would be better off living in the public realm. Not looking to start a debate over whether or not this is correct for WotC to implement this way or anything of the sort, merely looking to add to the list of differences between IRL and MTGO tournaments (Top 8 Play / Draw I'm looking at you). As far as I can tell this is accurate, but does not reflect any discrepancies that are caused by results outside of the norm (draws are a particular area that I cannot confirm or deny any difference as I don't know if this is even possible in the MTGO tournament structure.)

The differences form the MTR Tie Breaker Explanation appendix are as follows:

  1. The minimum match win percentage for a player is 0.3333 (As opposed to 0.33 in the MTR)
  2. The rounding precision is 4 decimal places
  3. Bye's count as 1 game won in the Game Win Percentage calculation (As opposed to 2 game wins in the MTR), and are still ignored in the 'Opponents GWP' calculations.

I know these aren't huge differences, but due to the small size of the Vintage Challenge events I have seen all of these differences have an impact on the order of the top 32. Although I haven't seen a top 8, 16, or 32 group affected by this, it's likely to happen at some point.

Anyway.. that's all, thanks for letting me nerd out a little bit!