It isn't flawed because I was using the rule example as a metaphor and not a literal comparison. Each game in a competition should be conducted under the same conditions. I also disagree that goal line technology is used in the FA Cup as not all games can have it and it should be the same for VAR. Like I said, we could go out because VAR wasn't there to check, whilst Spurs could go through on a decision that was made with VAR. Hence, all 4 games are not being played using the same criteria.