I don't think that Alex Higgins' 69 is the best break in snooker. Let me explain why by analysing the break shot by shot. I'll be writting the break score first and commenting on the shot that got him the points.
1 - The first red is absolutely a rubbish shot. No position what so ever. Horrible shot.
4 - The shot on the green was a good pot. I don't think that he played to move the red from the cushion, I think that he just concentrated on the pot.
5 - Good pot, again not playing position. I do the same with those shots, play it with right hand spin to make the pot and hope that I'll land somewhere good. Difference is that I'm not a snooker legend, I'm a nobody.
12 - Great pot, I guess the position is decent as well for the first time on the break, I don't think that he could get to an easier red from the black.
13 - Good pot and ocne again horrible position play. He didn't get to the pink for the left corner for the 2nd time in the break.
18 - The famous blue.. This shot I think describes this whole break. Great pot, rubbish position play. Yes, the pot itself is VERY difficult. Yes, he put loads and loads of backspin and left handside spin. BUT: did he really need to? I don't think so, he didn't get to an easy red. He had the whole right side of the table to land on an easy red for the left corner, but he overhit it and landed in the middle of the table behind the reds...
19 - Great pot and at last a good positional shot as well. He really couldn't mess the position of this shot up, it was all about the pot, the position was automatic.
26 - Easy pot, decent position as well. I would had played with a touch more backspin so he wouldn't need the rest for the next shot, but ok, doesn't matter.
27 - Good pot with the rest, position was automatic again.
34 - Nice position.
35 - Nice pot, automatic position.
The rest are the colors. He didn't messed that up, but really, I don't think that clearing the colors are concidered as great shots by professionals. This is the most basic routine ever. So really this break isn't concidered by many as "the best break in snooker" because of the colors, but because of the shots before them.
As you can see from my comments I didn't like the position play of Higgins. And because of this reason I don't think that this break should be concidered as "the best break in snooker" and I'll go even further to say that I wouldn't concidered this as one of the top 5 or 10 best breaks. I get that the preasure was immense and the importance of this frame was tremendous, BUT a) purelly from a break building perspective this is NOT a good break, horrible cue ball control and b) don't try and act that this was the first time a player was on preasure and he had one opotrunity to win a massive match. Yeah, the conditions were tough, but he wasn't the only one who have ever experienced this and I refuse to believe that there aren't other players who could play simple position even with extreme preasure on them.
In my eyes a great break is a break that is so well played that there is no need to play difficult shots (this obviusly changes a little when the balls are awkward, BUT in the case of Higgins 69 nearly all the balls were out in the open with the only exeption being a red on the left cushion.). Whatch again Ronnie's fastest 147. You watch all the shots and think "what's so special here? I could have made this shot!!". That's because he lands his cue ball exactly where he wants so all he has are easy pots. No need for a long blue because he missed position on the pink by 20 inches, no need to slam the blue in with extreme low left and miss the reds by half a table, no anything like that. Control the cue ball with pressision and only have easy pots.