For business certainty, there's a point at which, if there are problems on a go-forward basis, I would think you could capture that with abuse of dominance, because the issue of substantially lessening and preventing competition is in both the merger section and in the abuse of dominance section.
I think if there are problems five years down the road, the abuse section might be the better way to deal with it than to try to unscramble a transaction from years ago.