I agree completely, but I must add, that if Pool was in Olympics at 2008, Efren would won that - then he would retire with peaceful mind.
Actually, if Pool became Olympic Sport after couple of years from now, Efren would still win it.
I know the next Olympic year would be 2012, even then Efren might still win, but this is hypotethical anyway as this is not happening.
Everytime Efren has challenged HIMself, he has won. (Actually, he lost the first (and only) Philippine Open at 2003 to Mika, 12-13, which really bugged him..)
But still:
When Matchroomsports organized the first WPC (at 1999), it was by far the biggest and most exiting tournament ever held - Efren won.
When there was this mammoth 9-ball tournament at Japan 2001, where winner got by far the biggest paycheck ever 165 000$(that time) - Efren won. (some rumours said there were 800 participants, don't know for sure..)
When there were the first 8-ball WPC at the Emirates, at 2004 - Efren won. (eventhough the money wasn't enormous, it was a big Title with all the best players, and the official WC Crown.)
When there was the first IPT tournament, the King Of The Hill (2005), and the biggest payday ever - Efren won.
When there was the first IPT World Open (2006) and by far the biggest Payday (again) - Efren won (again).
(The NA Open, which Thorsten won and Effie came 5th, was just a warm up for the Reno World Open

)
Efren nature is not a 'Title defender' (in Majors), nor even 'Title renewer'(in Majors again).
One time, and in most of the cases the first time, is for him. Then he's motivated and hungry for the win. He want's the World to know.
I've noticed already many years ago, that at the WPC, Efren really hasn't been a threat to win it at all. (I guess same with the US Open.) He has won it already once, he's content about it, and the rest of the field are much more hungry.
In smaller tournaments, like San Miguel Asian Tour couple of years back, he used to dominate, cos he just played for fun without too much pressure in anything.
Also, One Pocket is different thing, as he really seems to like it in his late years, the DCC is only once a year, so he does challenge him self year after year to win it. Also, in that game, he's just so much better than the rest.
I don't want to jinx him, but I believe that when he loses first time the 1-P title there for someone, he'll lose some inspiration for that also, and he will be much easier to win after that in 1-P (the age factor..).