Lot’s of good points have been made on this thread. As an Episcopalian (and former big-C Catholic), my guess is that any and all defections to Rome will be on an individual basis only–not by entire groups, national Anglican Churches, etc. It would be very hard to get an entire group to make the switch if the clergy, and especially the bishops, had any concerns about their status following reunification. (some of these points were addressed by others earlier in the thread)
Would increased availability of Anglican Use liturgies help attract disgruntled Anglicans? Unless there are already a lot of Catholics interested in attending Anglican Use liturgy, I doubt it would be a good investment (though I’d like to see one). In the US at least, there’s a large concentration of disaffected TEC members in South. Generalizations are always dangerous, but my experience there was that those folks would not be heading Rome-wards any time soon, and would therefore not be too likely to make the switch. Some of the other areas with a lot of dissent (the Dio of Springfield IL comes to mind), may or may not be more RC-friendly, but have never had large a large Episco-presence. So I can’t see that would but a good investment, either.
Let’s face it, there are a lot of similarites between our worship, hierarchical structures, etc. Yet, even if we could take back some of the innovations of the last 50-100 years or so (birth control, allowing divorced/remarried bishops, women priests, acceptance of homosexuality), there were still plenty of doctrinal differences back then between our churches, and there still are. Yet, these people have stayed in the Anglican or Continuing Churches up to this point without converting to the Catholic church. So we may see lot’s of people running away from the the Episcopal Church and other liberal churches in the Anglican Communion, but as Catholics, you really want to be sure that they are running toward you, and not just away from their previous churches.