I have to reiterate what the others have said - a little boring, but at least a bit different to the usual fayre - which is exactly what we will get again next week.
As for Merlin's decision, I didn't think he would do that. His vision wasn't clear as regards to the time it happened, so it could be long in the future. Mordred has already saved Arthur's life twice, so why not twice again before being responsible for his death. Even Gaius, who he trusts, gave him the same advice. However, he carries on doing whatever the Dragon tells him to do. He has no backbone. He castigates Arthur on the difference between destiny and fate, but he seems unable to separate them when it applies to himself.