Linguists tend to be a pedantic lot. Faced with a good old bulleted list, the amount of time that goes into discussing the relative merits of introductory colons, initial capitals, and final full stops can be quite phenomenal.
It's a question of finding the right style.
Grammar is open to opinions as well, of course. One example might be whether the cricket correspondent should write 'England is all out' or 'England are all out' after the batting has collapsed yet again. The nature of style, though, means that it is always open to variation.
Faced with such choices, many people develop strong personal preferences and strong pet peeves in stylistic issues. One such issue is the use and misuse of emphasis.
There are several ways to emphasise a word or phrase, especially with software that can produce italicised and bold text at a single click. In some contexts, however, one form of emphasis might seem more appropriate than another.
Most web-savvy individuals realise that writing in all capitals is seen as the anti-social equivalent of shouting. Others realise that an underlined word on-screen may be misinterpreted as a clickable link. Italics, boldface, inverted commas, size, font, and maybe even colour can also all serve to highlight words for different effects.
One thing that does get a trifle irritating, though, is the use of multiple emphasis on one word. If a word needs that much emphasis, maybe the text is not doing the job in the first place.