I wouldn't be surprised if there was a lost subtext of Church politics and jockeying for power. However, I recommend reading more about the Chalcedonian split before putting it in those terms. This conflict could be traced back further than Chalcedon, even back to Nestorius and Cyril (of Egypt) and the Second Ecumenical Council.Back in 451 AD, the Egyptian Church split with the Roman/Greek Church. The split came after the Chalcedon council created a new patriarchy in Constantinople with greater authority than the existing one in Alexandria, Egypt. I suspect that change was far more important in the split than theological fine points.
- Nestorius theorized that Christ had two hypostases, and Cyril denied this, saying that two hypostases would entail that Christ had two persons. Nestorius denied that his theory entailed that Christ had two persons. I am open-minded on whether Cyril interpreted Nestorius correctly or not, since two hypostases could be translated as either two substances or two subsistences, and the Churches have agreed that Christ has two substances. But in any case the 2nd Ecumenical Council decided that Cyril was correct and that Christ had only two hypostases.
- The conflict led over into Cyril debating with the Antiochian school over whether Christ had two natures or just one. The Antiochians said Christ had two, Cyril asserted that Christ had one (miaphysia), and eventually Cyril said that he (Cyril) and the Antiochians were really in agreement, and he smoothed relations over. Problem averted? Unfortunately not, because...
- ... Cyril's successors in Egypt asserted that it was a heresy to teach that Christ had two natures. Meanwhile, the Patriach of Constantinople deposed Eutyches for claiming, among other things, that Christ didn't have two natures. Eutyches' statements included: Christ had two natures before the union, but only one afterward.
- Pat. DIoscorus in Egypt supported Eutyches, called another council in Ephesus and reinstated Eutyches and excommunicated the Patriarch of Constantinople.
- The EO and RC side called Chalcedon to teach that Christ had two natures.