Their engagement -- is it rather artificially contrived to clear the way for Fred and Anne – or is it a credible, possibly very sweet, or perhaps slightly bittersweet, romance between them?

Anne’s view of Capt B in chap 18 –
'Captain Benwick was not inconsolable. That was a point which Anne had not been able to avoid suspecting before … confirm the idea of his having felt some dawning of tenderness toward herself. … She was persuaded that any tolerably pleasing young woman who had listened and seemed to feel for him would have received the same compliment. He had an affectionate heart. He must love somebody.'

Capt Wentworth’s view of Louisa to Anne in chap 20 –
'"I regard Louisa Musgrove as a very amiable, sweet-tempered girl, and not deficient in understanding, but Benwick is something more. He is a clever man, a reading man; and I confess that I do consider his attaching himself to her with some surprise ... A man like him, in his situation! With a heart pierced, wounded, almost broken! Fanny Harville was a very superior creature ..."'

Capt W’s explanation in chap 23 of his actions after what happened at Lyme –
'"I found," said he, "that I was considered by Harville an engaged man! ... I was startled and shocked. To a degree, I could contradict this instantly; but when I began to reflect that others might have felt the same -- her own family, nay, perhaps herself …”
He found too late, in short, that he had entangled himself ... It determined him to leave Lyme, and await her complete recovery elsewhere. He would gladly weaken, by any fair means, whatever feelings or speculations concerning him might exist’.

I wonder -- when FW "instantly" contradicted the view that he was engaged, he could have done so very strongly, and Benwick who was also present, must have realized that his friend regretted entangling himself. It might have aroused some interest and sympathy in him regarding Louisa, and when Louisa was recovering, they were very much thrown together. FW’s “fair means” of leaving Lyme and staying away could have indicated to Louisa that he had no serious interest in her. There came to be mutual sympathy between them, and mutual consolation, Benwick having lost his first love to death, and Louisa losing hers because he was not really interested. Benwick could also feel that the superior Fanny Harville might always remain in his memory, but that there could be none other like her, and that he should rally and console himself with a “very amiable, sweet tempered girl” who had herself been disappointed in her first love.

What do others think -- is the Louisa-Benwick romance credible?