I am struck by the notion that Frederick (we're already on a first name basis!) may not have been looking around for a ship if Anne had not retracted her acceptance. Is Anne's prudence and self sacrificing the reason for his success so quickly and at that particular time?

".... It was a great object with me, at that time, to be at sea: a very great object; I wanted to be doing something."

"To be sure you did. What should a young fellow like you do ashore for half a year together? If a man has not a wife, he soon wants to be afloat again."

.... and later...

I had the good luck in my passage home, the next autumn, to fall in with the very French frigate I wanted.

Had Anne and Frederick remained engaged, would he have captured a frigate by that time or even had his own command? Would he have been on the Asp?

Was it better for them to be truly apart rather than delaying his career and opportunities? Was the express lack of money a good motivator?

Anne did it for him.

The belief of being prudent, and self-denying principally for his advantage, was her chief consolation