This was prompted by another post on SE. "I have the exact same problem"
I know that 'the exact' is truly horrible used in that way, & that it should be 'exactly the'.
What I don't know is what makes it horrible, grammatically.
My long-forgotten English classes in school would make me think exactly would be an adverb, like "John runs quickly", just because of the -ly ending but it doesn't ring true. Either it a) doesn't obviously link to any attendant verb in the original example, or b) the attendant verb is to be = have, or c) I'm barking up completely the wrong tree.
The more I analyse it, the deeper the hole I appear to dig for myself.
Best Answer
I'm not sure why OP thinks the exact same is a "truly horrible" usage. It's perfectly natural to ordinary native speakers, but here on painintheenglish.com is the somewhat obscure rationale as to why some pedantic grammarians object to it...
If you follow that link, you'll see quite a few comments after the above text. They mostly seem to be from competent native speakers, and the vast majority of them defend the usage (either by saying it's idiomatically ubiquitous, so by definition it's valid, or by taking issue with the adverb/adjective distinction as used in the argument).
Note that the exact same/exactly the same issue has been covered on ELU by The use of “exact same” and Shouldn't “the exact same” always be “exactly the same”?. Also note that because the exact same is more recent, and much less common than exactly the same people tend to look for a subtle semantic distinction.
In most contexts I don't think there is any difference, but non-standard phrasing = non-standard meaning is an established aspect of English, so it could make a difference if, for example, you used both within the same conversation...