Ye I got that one. Had this blue bar around the screen too. Even as a kid I noticed there was something off with the music and speed compared to Sonic 2 and which seemed to be a better port.
Yeah, but if you're timing a speedrun using a real world clock, then the PAL version may actually be harder because it runs slower.
I wouldn't be surprised if there are games out there with a visible in game timer which has been adjusted for PAL while the rest of the game is still slow as well...
edit: Oh yeah, I also just recalled that the PAL version of the PlayStation port of Doom was PAL fixed in a funny way:
The game timer still ticks at the same rate as in the NTSC version (so it's slightly too slow now in PAL), but the player's movement speed has been increased, so you can sometimes make jumps which just aren't possible on NTSC or the original PC version.
Durations for frames (states) of monsters and the player's weapons which are counted in game timer ticks have been adjusted inconsistently as well, which results in at least the shotgun being more powerful since it's faster relative to everything else in the gameworld.
I don't remember whether projectile speeds were adjusted. Monster projectiles now being slightly faster (relatively) would tip the scale a bit the other way.
So even a supposedly PAL fixed game be easier than the NTSC original, or it can just be different as well.