If

·conj Whether;

— in dependent questions.

II. If ·conj In case that; granting, allowing, or supposing that;

— introducing a condition or supposition.

if so be as how
A vulgar expression used by uneducated people in the interior parts of this country and in England. ...

Dictionary of American Words And Phrases by John Russell Bartlett.
looking as if one could not help it
Looking like a simpleton, or as if one could not say boh! to a goose. ...

Dictionary of The Vulgar Tongue by Francis Grose