Pro Tour Return to Ravnica
Quarterfinals:
Willy Edel vs. David Ochoa
Willy Edel would have won the match 2-1 rather than Ochoa coming back and winning the match after starting 0-2.
Pedro Carvalho vs. Stanislave Cifka:
Same result
Shi Tian Lee vs. Eduardo Sajgalik
Same result
Kevin Chew vs. Yuuya Watanabe
Same Result
Semifinals:
Shi Tian Lee vs. Stanislave Cifka
Same result
Yuuya Watanabe vs. David Ochoa
This match would not have happened, but if it did under the new rules the same result would have occurred.
Overall Different Results: 1
Pro Tour Gatecrash
Quarterfinals:
Ben Stark vs. Steven Mann
Same result
Joel Larsson vs, Gerry Thompson
Same result
Owen Turtenwald vs. Eric Froehlich
Same result
Melissa DeTora vs. Tom Martell
Same result
Semifinals:
Eric Froehlich vs. Tom Martell
Same result
Joel Larsson vs. Ben Stark
Ben Stark would have won the match 2-1 and proceeded to the finals vs. Tom Martell. During the course of the PT, Ben Stark was 2-0 vs The Aristocrats (with one of those wins coming against Martell), so it's somewhat probable that with these rules in place the winner of this PT would have been Stark.
Overall different results: 1 (2 total)
Pro Tour Dragon's Maze
Quarterfinals
Craig Wescoe vs. Andrejs Prost
Wescoe, the eventual Pro Tour winner would have lost 2-1 to Andrejs. Andrejs instead would have played vs. Utter-Leyton's boros deck in the semis. During this T8 match, Utter-Leyton tweeted
"This quarterfinal between Prost and Wescoe is a huge sweat for me, don't think I can possibly win against Wescoe"
Utter-Leyton would possibly have a semifinals and finals match against Esper control, where he obviously felt confident about his chances.
Andrew Shrout vs. Josh Utter-Leyton
Same result
Rob Castellon vs. Dusty Ochoa
Same result
Makihito Mihara vs. Matej Zatlkaj
Matej would have won this game in 3, but this would have still left the semifinal match as an Esper mirror.
Semifinals
Dusty Ochoa vs. Makihito Mihara
Mihara would have won the match 2-1.
Josh Utter-Leyton vs. Craig Wescoe
Match would not have happened, but it would have the same result as Wescoe was up 2-1 at the end of game 3.
Overall different results: 3 (5 total)
Pro Tour Theros
Quarterfinals
Jeremy Dezani vs. Kamiel Cornelissen
Same result
Makihito Mihara vs. Paul Rietzl
Reitzl would have won (and Mihara would be 1-1 in terms of how he was affected by the changes)
Sam Black vs. Kentarou Yamamoto
Same result
Pieree Dagen vs. Guillaume Wafo-Tapa
Same result.
Semifinals
Jeremy Dezani vs. Makihito Mihara
Same result
Sam Black vs. Pieree Dagen
Same result
Overall different results: 1 (6 total)
Biggest losers if the new system was used for the last year: Craig Wescoe, maybe Tom Martell
Biggest winners if the new system was used for the last year: Josh Utter-Leyton, maybe Ben Stark
tl;dr: 6 matches would have changed with one PT having a guaranteed different winner (as Wescoe would have lost in the quarters) and one having a likely different winner (as Ben Stark was favored against Martell's Aristocrats)