Sorry, I moved the file with the link accidentally
Try This http://tinyurl.com/6eqxncf
The problem is very clear on the ipad and i have made a video so that you can see it. I now see why it does not show on an emulator browser because it only occurs when you are zoomed in on a tablet or you have scrolled the screen up or down.
the tooltip position is alway correct when the page loads. - this is because the browser is at the top of the page. If you scroll down the page (which you can only do by zooming first as the ipad scales the window automatically on loading a page) then the tooltip always appears incorrectly as it is positioned relative to the top of the browser and not the top of the page.
So as long as you are at the very top of a page, no matter what zoom level you pick the tooltip appears in the correct place because the top left corner of the page (top,left) = (0,0) and the browser window top left=(0,0).
Once you scroll down the page, the top left of the page now has new coords, say (+100px,0) ie the page is scrolled down by 100px, however the tootip still appears position from a reference of (0,0) and not the new positioning reference of (100,0) thus the tooltip is 100px misaligned
Watch this video. Its a bad version of a ipad commercial :)