A solid, well-reasoned, post, but I'd like to offer that there are other considerations when it comes to Efren and Earl.
Efren's efforts are legendary, in part, because he advanced the science of the game. No idea how old you are, but when Efren came to America, he was employing some shots and strategies never seen before. He introduced us to many of the shots that would gradually enter the arsenals of most of the top players. Kick shots, 2-way sots, safeties --- Efren seemed to know shots that nobody else knew. At 9ball, but even more so at 1-pocket, he got everybody thinking differently about how the game can and should be played. Efren's greatness is partly tied to his performance and partly tied to his groundbreaking style of play, which integrated billiard knowledge into pool in a new way. His imagination set the stage for greater development of the theory underlying the game. Another amazing thing about Efren is the speed at which he learned and mastered new games. He had never played straight pool but tried his hand at the 1993 World 14.1 championships and medaled. He had never focused on 8ball, but when the IPT came along in 2006, he won the biggest prize ever paid in 8ball, which was $500,000. He had never tried one pocket until he learned much of it from, among others, Billy Incardona and Fred Bentivegna, and it wasn't long before, in Billy's words, he clearly understood things that even they didn't. He went on to be the greatest ever one-pocket player.
Earl's legend is another matter. Though it was played before, 9ball only became a major competitive discipline in 1976. For most of us, Earl came onto our radar in 1980 as a 19-year-old. He offered a brand of 9ball never seen before, a game based more on power than anything else. He was, unquestionably, the first to ever master the nine-ball break, and because of it, he sat opponents down for racks at a time more than anyone that came before him. It gave him a top gear that nobody could match. He was known for often dismissing the greatest of champions by very lopsided scores in competition. In short, Earl can be credited with ushering in the era of power 9ball that is still going strong.
Hence, it is true that if you watch old footage of Earl at 9ball, you will probably not think he played like the current edition of Filler, and I won't disagree. Similarly, if you watched footage of Efren at 1-pocket, you'd wonder whether he'd have beaten modern day Shane, Gorst or Filler at one pocket. I'd suggest, however, that a wider lens is needed to made these kinds of assessments. Earl and Efren were foundational players that introdcued a new type of pool to us, and part of their greatness is tied to having done so.
Just some food for thought.
