I don't really see how that argument could hold any water to be honest.
The separation between the churches was both gradual and with very ancient roots, as soon as the Byzantines couldn't keep the Papacy under control the Western church started behaving independently from Constantinople, and the only thing that kept the division from becoming official as early as the 8/9th century was that neither Catholics nor Orthodoxs wanted to split the universal church (although the division was actually already underway).