I don't agree with the poster you quoted at all, Vicomte13 (not that it matters, since that was posted over a decade ago; I kinda doubt they're still around to explain why they think that), but regarding the rest of what you said: if you're at one of our churches in the West, chances are they'll have pews (I've never been to a Coptic church that didn't have them, though I don't know about the other churches in our communion). You can sit down if you need to. It's not normative, but neither is forcing people who are in pain to the point of not being able to concentrate to continue standing as some kind of endurance test. Of course, it is best and customary to stand at least for the gospel readings, during certain deacon's proclamations (e.g., the introductions to the readings), to receive the blessing from the priest when he censes the church or places the cross upon the people's heads, but nobody is going to throw you out of church because your feet hurt and you're not used to 3 hour liturgies. It's something you get used to after a while anyway.
In the Latin Rite, we also stand for all prayers per se (of course, the whole Mass is a prayer, even the readings - the whole liturgy is a prayer, in truth, but some parts are more solemn than others), for the Kyrie and the Gloria, for the Gospel, for various incantantions - we kneel during the preparation of the gifts and communion, and stand for the entrances and exits of the priest. Whenever there is incense, we stand, because incense solemnizes things.
We don't stand for the homily, or the offertory, or any of the readings other than the Gospel (and the readings and the homily are the most time consuming parts of the Liturgy of the Mass).
Interestingly, as Eastern Orthodoxy has come West and more people have joined it, the EO churches that try to appeal to Westerners rooted around in the archives and discovered that back in the early era, when the East and West were still united, the Westerns were ALWAYS more restless and always had shorter services. The Liturgy of St. Gregory dates from the 300s AD, and was traditionally used in the West. It was revived by the Eastern Orthodox for Western liturgies. It's about an hour long.
Easterners were sophisticated urban dwellers for thousands of years, while Westerners outside of Rome back in the Roman Empire were still fishermen and farmers and foresters, rather rough working folk not accustomed to sitting still.
And the Catholic and Orthodox liturgy of the West reflected that. The Catholic Mass, and the Orthodox Liturgy of St. Gregory, are about an hour long.
I suppose that the Orthodox stand during the homily. I would find that annoying and it would make me think about my feet, even for an hour. It seems utterly proper to me to stand for processionals, recessionals, prayers, incense, the singings of Glorias and Kyries. And it seems especially proper to kneel during the blessing of the sacraments, and whenever the eucharist is exposed.
But standing for awhile gets uncomfortable, so if you really want me to LISTEN TO the readings and the priest's homily, best to let me sit. By standing for the Gospel and singing Allelujia, I think we're making the point that THIS is the very KERNEL of Scripture, so stand up straight and pay attention - all makes sense to me.
The Russian Orthodox liturgy was beautiful, certainly, and the logic of it made sense, even the do-everything-thrice aspect, which sort of felt like doing a liturgy for the Father, then doing it again for the Son, and doing it a third time for the Holy Spirit. I'm sure that's not what the Russians think they are doing, but that was what I reasoned out.
I agree with making things as glorious as possible for the Emperor of the Universe, and always appreciate Orthodoxy for that. But I used to dread the Christmas liturgy I'd always get invited to - not because it was so long (it was) - but because there I was a young, strong, fit military man, and standing on those stone floors for upwards of three hours was hurting my legs and feet. It was always an endurance contest, and I found that detracted.
Something confused me too - there was a point where they were handing out leavened bread, and I demurred therefrom, given that even though I think the Orthodox and Catholic religion are the same, I recognize that the Orthodox don't, so I did not want to raise offense by knowingly taking the eucharist when they could see I was obviously a Catholic (crossing myself "backwards", not understanding the Russian, etc.), but the congregation all around me INSISTED that I go take that bread. They urged it and insisted. When in Moscow, do as the Muscovites do, I guess. The eucharist is the eucharist - but my fear of giving offense by taking it when I thought they would think it was inappropriate was transformed into a desire to not offend my hosts. From my perspective, I had communion and that was that.
I noticed that they did not serve the communion in species of wine. In our church there is the bread (unleavened, of course) and then the COMMON cup of wine. They wipe the rim and turn it a quarter turn with each drinker. I drink it, of course, but I find the idea of 500 of us drinking from the same cup one after another kind of squidgy. I make a scruple of NOT taking the wine if I have even a slight cough, but others don't seem always to be as concerned.
I think that thing that particularly draws me to Oriental Orthodoxy, particularly in its Ethiopian form, is the extended canon of Scripture. The book of Enoch, in particular, is only available there. St. Jude refers to Enoch by name, and once I read it, I realized that Christ uses language that is in there on several occasions. So, is it Scripture?
Well, a part of the Church that's as old as any other has it, and the Church was in unity for over 400 years with that being part of the Scripture in one part, so maybe it is, even if the West didn't adopt it.
Certainly the Scriptures take on a different set of meanings and understandings when Enoch is in the Canon.
I don't think Enoch is in the Coptic Canon, but given that the Copts are, I believe, in communion with the Ethiopians, I guess that this difference is not important enough to make a division.
In any case, I would like to see the Church come back together - Latin, Greek and Oriental. Christ prayed for unity, and I myself have never seen anything in Eastern Orthodoxy or Catholicism that would be sufficient to override Christ's call for unity.
I get that the question of Papal authority is important (though Catholics themselves tend to personally honor it more in the breach), the whole "filioque" issue strikes me as another misunderstanding of an earlier age, and Oriental Orthodoxy has not been, to my knowledge, the focus of any particularly fierce Western-Oriental fight. The Latins and the Greeks have more history (the sacking of Constantinople by the 4th Crusade ranks up there with the burning of St. Joan of Arc as bad acts of the distant past that just make one wince), but that was them and then, and not us and now.
I find Church fights to be particularly distressing, and wish we'd remember that Jesus firmly called us to unity.
I think that the Catholics are wrong for forbidding priests to marry, and the Greeks are wrong for forbidding bishops to marry. St. Peter was married - Jesus healed his mother-in-law - and that should be a strong enough example to override the nonsense that says otherwise. Jesus held out celibacy as an ideal, but he did not enforce that on the highest of the high clergy as a disciplinary matter. I think we mar the body of Christ when we do.
But what do I know?