There are plenty of dominant performances in MMA, but what separates the elite from the good or great is consistency. When Chuck defended his belt seven times, taking no damage in the process, he was an elite champion. Same with Hughes, GSP, Silva, Fedor.
Jones similarly has consistently imposed his will regardless of whom he's fighting or where the fight is (striking, clinch, shots, ground). He's sustained ZERO damage in his career, and hasn't had an off day of note. That is consistency, and that is elite.
Shogun was elite in his Pride days; there's no questioning that. But is he elite now? He is 3-3 in the UFC. One of those 3 wins is again a deteriorated Mark Coleman, another is against a shell of Chuck Lidell. He beat Machida fair and square, that is impressive. But he lost to Forrest, lost an iffy decision to Machida during which he inflicted zero damage on Machida, and was obliterated last night. He may or may not be permanently compromised from knee injuries, but the decrease in performance due to injuries, as unfair as it seems, is part of the greater equation in determining how good you currently are. Shogun does not have the consistency anymore to make him elite. To quote a song, "He once was, but now he's not." That's not actually a song but it's fitting.