E.g.:
The stutterer:
Speech not fluent
Begins early
Generally ends by 16
Worse with anxiety.
A book full of time-worn clichés. Which is actually its strength. You read it and you say, "Ok, if it's like that, my character starts stuttering at the age of 18. And it's only bad when she's really happy, otherwise when she's stressed, she's a poet. Na na na na na, nerrr. Ok! Let's go: who, what, where, when, why?" If characters are cocktails then this is a sort of recipe book. Only the best cocktails never follow the recipe but the barman's tush. (Some would say: if you need a recipe book you don't know how to cook. But then again it's reassuring to know which direction to head when looking for the market. Etc.)
I've enjoyed bouncing off this book. The intro is over-earnest self-important puff, chapter one is a disclaimer ("Good characters break out of stereotypes"), and the rest is essentially one big list of clichés, prejudices, and déjà-vues, all packed up in one book, to play with and have fun. The alcoholic Islamist alchemist. The narcissist, post-divorce, tennis-playing, insomniac child. Bring 'em on.