There's rare and then there's idiosyncratic.

Maybe they miswrote. But if I accept what they say; then the word "acrasial" was employed for one calendar year or less. I think its safe to say that a word used for less than a year isn't really a part of the language.

One problem is the love of wordplay. The Victorians in particular were inclined to take an interest in curious and rare words, even if they had to invent them. Not every invention became a part of the language.

This also lead them to search in the annals of history for archaisms. Unfortunately, they also sometimes found a long dead someone else's word games. It would appear that many of the now famous collective nouns for animals ( eg. a "murder" of crows ) was neither employed prior to its first citation, nor for the centuries afterwards until unearthed by curious Victorians. Since language is functional, the unemployed word, even if jotted by a dead abbot, does not enter the language.

Maybe "acrasial" was used for long enough to be English. But in that case their entry is in error.

( See also failed attempts to coin neologisms and programmes of language "reform." A single newspaper editor's insistence on idiosyncratic usage is not itself sufficient. )

As for converting phobias to philias, I'm all for it. I'd like to cure my Acrophobia. And if I was spontaneously aroused by heights; so much the better. Although the moaning might distract the others on the observation deck of the Empire State Building.

Dante