@Preston:
I think you are the one who is now misinterpreting my words. I meant that if they had figured out the disparity, there wouldn't BE a disparity. And yeah, if you see in my original comment, I also agreed that 4kids is probably the primary factor. Which brings me back to my original point; if it's obvious (to us, then why not them?) that 4kids pretty much dented OP's rep, then why wouldn't Viz try to jettison all traces of 4kids' influence, which includes random name changes?
Also, I forgot to point this out, but a former Viz employee presented a very good reason for why exactly Viz wants to do a speed-up:
link: http://manga.jadedragononline.com/?p=1602
Well first off there's a difference between not being popular as it could be and having a disparity in popularity between the U.S.A. and America. Now could "One Piece" be more popular in America? Of course, "Dragonball" and "Naruto" and "Bleach" have all done really well here, I don't see why "One Piece" can't reach a similar level (although the success of "Dragonball" and "Dragonball Z" in terms of manga sales is on a similar of "One Piece" as of now, of course the former having a more successful anime run helped out more. "One Piece" is also debuting at a time when manga in general has become more popular in this country, they're kind of even). And "One Piece" has been gradually getting closer to that level, even before this speed-up was announced.
And you've gotta give 4Kids credit where credit is due. They have been one of the main reasons "One Piece" hasn't really caught on here, but when the anime was on Toonami it did well. Any exposure is good exposure and T.V. has helped manga sales, from when the 4Kids dub got on Toonami till when FUNimation started up. So I won't go over why 4Kids hurt the property since we've all been down that road, but they didn't cause a disparity. There are plenty of reasons why "One Piece" probably won't reach a level similar to what's in Japan, from American tastes to grassroots fan-following to being in the right place at the right time.
Now looking at what VIZ is doing, it certainly looks like they're understanding the disparity. "One Piece" suffers from pacing problems combined with a release schedule that's held back and slowed by a monthly magazine circulation, which I believe has led to less American readers getting into the series. VIZ has chosen a good time to start the speed-up, right when fan demand has reached it's pique and to tie-in with the FUNimation simulcast (that's definitely something I imagine VIZ would mention themselves had it not been put on hold). Erasing the 4Kids terms and names would do nothing but please the core fans, who are good enough for VIZ right now since "One Piece" has been consistently selling well already. What will matter is getting in a bunch of new fans who aren't really familiar with the original terminology in the first place. In fact there might be readers who got into the series when they started using stuff like Zolo, and re-changing the names will just make them go "WTF?". And let's not kid ourselves, the changed names weren't the reason 4Kids' dub sucked so hard.