You are kinda missing the point. The Sith are an offshoot of the Jedi, so they share many of the same practices. When a Jedi is done training one apprentice, he can take on another, but only one at a time (remember in TPM?). The Sith focus solely on one apprentice, who eventually replaces his master, and then takes on his own apprentice. Prior to this, the Sith were building up their numbers, much as the Jedi had done, but infighting killed off many of the Sith, thus the "Rule of Two" was born.
Either way, I don't see how this is a valid argument for showing how judgemental and arrogant the Jedi are. Are you implying that the "Rule of Two" makes the Sith less judgemental and arrogant?