I think you are actually comparing apples to oranges, though I understand the nature and spirit of what you say.
All of the various factions that exist within Catholicism, but I must exclude the actual schismatic groups here, represent the multifaceted modus operandi that is the Roman Catholic Church. Traditionalists can and do worship side by side with modernists; liberals worship side by side with conservatives. You don't have liberal bishops going off on a whim and creating their own "Genuine Catholic Church of America": there remains one Roman Catholic Church so that when you walk into your neighborhood Catholic Church you can be 99.9% certain that it is in communion with Rome and that, yes, Pope Benedict XVI will be prayed for audibly as part of the communion prayers.
Here's the deal: the last major "big event" within Catholicism was Vatican II. I say this because you may have traditional Catholics who like the Tridentine Mass and have the blessing of the bishop to worship as such, you have the moderates who use the Novus Ordo and leave it at that, and you have the liberals who desire to, "continue with the spirit of Vatican II.
Suffice to say Vatican II has had its impact on Catholicism, yet those who remained in Communion with the Bishop of Rome adjusted on the parish level as they saw fit.
Yet, those who were quite prideful of themselves and made idols of their various idiosyncratic worship styles broke Communion (minus the moderates) and formed their own group; naturally there are Traditional
ist Catholics who maintain the pre-Vatican II ways and Liberal
ist Catholics who have effectively become Protestant.
Okay, now to Orthodoxy:
The last major "big event" within Orthodoxy was the adoption of the Revised Julian Calendar in the 1920s - minus some Slavic countries and the Patriarchate of Jerusalem who maintained the Julian Calendar. There are those who are on the New/Old Calendars who have chosen either calendar with the blessing of their bishop because the bishop, or the jurisdiction as the case may be in North America, has a "default choice" if you will, but will typically grant a blessing to those who wish to be on the other calendar. Example: the Orthodox Church in America. The OCA's default choice is to be on the New Calendar, but there are those who are on the Old Calendar who are still in Communion with the rest of the Church - Just like there are those Roman Catholics who use this mass or that mass who remain in Communion with the rest of the Church.
Just like with Catholicism's last "big event" of Vatican II there are those who splintered away because they made an idol of the calendar - just like those in Catholicism who made an idol of their mass. Romania and Greece adopted the New Calendar, yet there are Old Calendar
ists who are not a part of the Church in either country and who are not even in Communion with each other!
So, there are divisions every which way you turn. A great deal of discussing such things has to do with terminology. Traditional Catholics are not the same as Traditional
ists; jurisdictions on the Old Calendar are not the same as Old Calendar
ists. The various Old Calendar
ist organizations typically revolve around the personality of an individual just like the various Traditional
ists revolve around an individual as well and whenever that individual dies than the organization typically falls apart. But the main point is that it all has to do with pride and disobedience because the greatest virtue is obedience. I remember reading about one so-called "Genuine Orthodox" cult which began when a priest was accused of sexually abusing some minors. What did he do? He was so full of himself that he cried "ecumenism!", declared himself a bishop, moved to another state and began a cult! He hasn't died yet, but I'm willing to be that when he does his cult will fall apart quickly.
The reason why crying "ecumenism!" in Orthodoxy is considered a powerful thing is because the greatest fear of most Orthodox outside of the traditionally Orthodox lands is that they would fall into the evil side of ecumenism and compromise the faith. All splinter groups, be they from Catholicism or Orthodoxy, are began by two primary factors: pride and some misconceived notion that the faith has been compromised. The schismatics from Orthodoxy have about as much effect on the Orthodox Church as the conclavists do on the Roman Catholic Church. And I hate to say this, but there are far more conclavist organizations than there are old calendarist organizations (although sometimes I think it may be a tie
).
Anyway, enough of my rambling...