1) I'm not sure what you mean by a 'semantic' issue. An exploit is an exploit, there's no such thing as "an exploit in name only". Intent is difficult (impossible) to prove 100%, but we can easily infer intent by observing people's actions. If your actions serve only to reset the mission list, you are exploiting.
You're speaking in absolutes, rather than in degrees. Fair enough. But if you insist on using absolutes, it is sloppy logic to "infer" intent. Without a dev comment on the actual intent -- it wouldn't technically be an exploit.
2) Whether or not that exploit is worth BW doing anything about is a different story. In this case, running a single tier one mission barely (if at all) takes longer than logging out and back in or rezoning, so I don't see it really being a problematic exploit. Most people (including myself) would probably get a better ROI by spending the time some people use to log out and back in paying more attention to the market -- I know I could make a lot more money than I do, but I'm lazy and I make enough.
3) An example of something WIA that goes beyond what the devs planned, but that they decided to let go, is using Legacy armor/weapons to pass Bound items from one char to another in your legacy. They said BoL was absolutely not designed for that, but that they didn't care that people use it for that. (As an aside, I consider that an exploit that I wish they would fix, as it essentially lets people gear up fresh 55 alts with BiS (78P) gear, which is why I think we see a lot of overgeared chars that don't seem to know their class in FPs).
I suppose. But doesn't it seem that adding the Gree Lightsaber (hilts being the only item not movable by legacy gear before that point) moved it past "the devs don't care if the exploit is used" to "the devs are actively making it easier to use that exploit"?
I'm also not convinced that shlepping mods via legacy is the reason for overgeared characters not knowing their class in FPs. This has been a problem LONG before this practice was widespread.
Anyway, I guess you could say that I think that it IS an exploit (as exploit is defined), but (since BW appears to know of it and accept people doing it) that it isn't an "exploit" in the sense of something that is "wrong".
That's fair to say. But remember that "exploit" is a very charged word in an MMO. It's usage in these types of games can hardly be separated from "wrong".