I recently received a question from Geneva on an old post about commonly-confused words asking me to clarify the difference between the words blatant and flagrant. The two words share a similar sense of the obvious, but are used to convey different senses. Consider this sentence (which I'd avoid in a real writing situation, as it's redundant and stilted):
Such a flagrant act show blatant disregard for established procedures.The word flagrant implies contempt rather than a simple lack of guile. While I may commit a blatant violation, it's possible that I am simply uncouth and thus unaware of the rules that I am breaking. If you label my transgression as flagrant, however, you mean that I not only broke that rule in an obvious way but that I did so because I either don't care about rules in general or that I purposely set out to break a particular rule that I find, for whatever reason, objectionable.
Blatant generally indicates an obvious act committed without taste or discretion. Flagrant, on the other hand, adds a taste of disdain to that same act, and perhaps a bit of flair. The difference between the two words lies in their implications. Thus, something could be blatantly flagrant, although your readers may blatantly turn away from your flagrant unwillingness to write well.