... your intent. I focused on your assertion that

"If Emma as the first lady of Highbury is willing ot sponsor Harriet and if H's looks, and pleasnat disposition are able to bring her a chance of marrying someone comfortably off and genteel, the girl would indeed be a fool to prefer being in Mrs Goddards set and ending up marrying the writing masters' son or noone at all.. Emma may have raised Harriet's expectation too high but stranger things have happened than that a well off man might marry a pretty girl who has litlte other to recommned her but her good looks and amialbe nature... and it seems ot me that Mr K is being dismissive of H's chances of rising a little further in the world. " (message 50739)

which says to me that you reject Mr. Knightley's assertion that it would be unwise for Harriet, both for her own comfort and that of her husband's, to marry an educated sensible gentleman.

As you pointed out yourself, there were men of her class who had become wealthy (in fact, Robert Martin is likely becoming one of those), who would not be so disastrously mismatched in education and sense.