I EARNESTLY MAINTAIN that whereas a good book affords the reader an ample number of pages – even chapters – to develop the point that is on a writer’s heart and there would be no need for occasional introductory CAPITAL LETTERS, in a relatively and mercifully brief social media post, they can serve a most effective purpose. They can inform the reader that the REALLY URGENT point is here (not 70-80 pages to come)!
I tend to shy away from posts written in all caps because it defeats the whole purpose of using them for emphasis but being super-sensitive to the point of being offended by any use of capital letters for the sake of brevity ought to be re-examined.
I hold a B.A., M.A. and Ph.D. in English and I can tell you that placing an *asterisk before a word does not tell billions of prospective readers that this is the CRITICAL PART that the author is leading up to.