Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
kindly (adv., adj.)
As adjective kindly is familiar and poses no problem: She’s a sweet, kindly old grandmother. As adverb, it has some fairly unproblematic uses, as in He kindly offered her his seat. When kindly means “please,” or “would you be so kind (or so good),” however, the situation becomes a bit more complicated. In Kindly step to the back of the bus and Kindly keep off the grass, kindly means “please,” but it’s a very emphatic sort of “please,” as the imperiousness of Kindly keep your distance demonstrates. And, as Kindly permit me to pass suggests, it is Formal and can deliberately distance the speaker from the person(s) addressed. See also FRIENDLY.
