@SilverGalford: Here's the thing with comics. Since there are SO many writers, you can't ask the original creator about a comic book character because not only did he create the character, but so did many others. Adding powers and story, etc. Take Superman for example. Jerry Siegel and Joe Shuster created the character, but DC gave him his powers.
I tend to see with manga writers that they really don't care to talk about a characters powers outside of what they write in their manga. I am sure Akira Toriyama has been asked about DBZ characters powers before, but from what I have seen there is nothing about just how fast they are. You can just assume from what the writer gave us already in the manga. There is no definite answer from the writer himself.
