Setting the pipeline request limit to anything above 8 is just stupid, since the browser protects servers from l33t tweaker d00dz by capping it internally to 8. Shows you how much testing the tweakers do to actually see what values are best :roll:.
Setting the initial paint delay to 0 is not necessarily bad, but it does slow things down. Basically (I"m simplifying this a lot, and even I don't understand it entirely), every time the browser gets more data from the server, it "reflows" the page (lays it out all over again). This takes some CPU time, and keeps the browser busy briefly. By waiting 250ms, it gets a decent amount of data up front, so it doesn't do dozens of reflows of a layout that's going to be changing radically over and over again as it gets more info. By setting it to 0, you're causing it to do a lot more work, and it WILL take longer to actually finish rendering the page. In theory, you could see some of the page a little earlier, but not much. Besides, in the first few ms, the page content is usually jumping around a lot (sometimes too much to read). If you have a really fast connection AND a fast PC (and the site you're visiting has good servers), this could improve the perceived speed.