I've done a side by side comparison of the cutscene in Sumo Stadium and the PAL version has shorter dialog. This cutscene alone saves about 10 seconds, in fact I had to retime the current PAL run because I did not account for the difference in time. (It's still WR as of this post).
I have both versions of the game that can run on the same console so I'll do a test of each cutscene to be sure but the difference is quite blatant.
I think the best approach now is to split the leaderboard into NTSC and PAL.