Not only that, wouldn't he be the first player ever to have won at least 5 titles at each of three Grand Slams? AO, USO and Wimby
He would indeed - and in fact that tally would mean that he would have accumulated more slam titles at just these 3 events than anybody has ever done at all 4 combined. As has been pointed out though, Federer already holds the record of having won 3 Grand Slam events at least 4 times - the 5x3 would be extending the record to new heights.
Semi-final #30 is coming up tomorrow and he stands just one away from Connors' all-time record of 31. He can also match Connors' record of 233 match wins in total at Grand Slam tournaments by beating Rafa.
I should also mention that Roger is on a 24 match unbeaten streak since the US Open in 2011. In his career he has so far compiled 7 streaks of 20+ match wins - again an Open Era record.