As I do have the Bravo 3 job, I can provide the authoritative answer.
I am tempted to say that you still have to go clockwise because you will invariably be in company with boats that just have a single prop, but I will give you the real reason instead.
In the case of the duoprop, you might think that either direction would be equally quick, but this is not the case as the comparative distance between Cape Wrath and Duncansby Head must be measured against the distance between Land's End and Dover when considered in conjunction with the effect of the rotation of the earth.
The longer you can travel with the rotational effect speeding you up, the better. That means travelling the longer W-E leg from east to west, ie Dover to Land's End.
That means even with a bravo 3 you go clockwise
This presupposes that the bravo 3 will hold together long enough