Frederic Johnston says: “Concerning the phrase ‘most perfect’ some question might be raised. ‘Perfect’ means, literally, ‘made through, to the end,’ ‘utterly finished,’ therefore, of supreme excellence. In that case, ‘more’ and ‘most’ perfect are meaningless. We are to remember, however, that the literal is not always the true meaning of a word. Thus ‘melancholy’ does not mean full of ‘black bile,’ but ‘gloomy’ for any reason. Moreover, it has of late been pointed out by the best authorities that the true sense of a word is not what it ought to mean, but what it does mean, in the mouths and ears of the upper half of the people. And there can be little doubt that ‘perfect,’ in this case, merely expresses great rather than supreme excellence. We may even say, further, that the word in its original sense could not be used without a qualifying word (as ‘nearly perfect’ for example) in a world in which nothing is utterly free from defect. To go about saying that things are ‘nearly perfect’ would be gross pedantry.”
For the sanction of literary usage see the quotations:
“It would be strange, doubtless, to call this the best of Burns’s writings: we mean to say, only, that it seems to us the most perfect of its kind as a piece of poetical composition strictly so called.”—Carlyle, Essay on Burns, referring to his poem “The Jolly Beggars.”
“Our battle is more full of names than yours,
Our men more perfect in the use of arms.”
—Shakespeare, 2 Hen. IV. iv. 1.
“Most perfect goodness.”—Cymbeline i. 7.
mought: Although recorded by the dictionaries as the imperfect of “may” and often used for might, the use is one which does sufficient violence to euphony to be characterized as undesirable.
muchly: Although formerly in vogue is now obsolete and stigmatized as slang, and as such to be avoided.