Just remember to use an appropriate text editor, like notepad++. I dont know how huge a difference it would make to edit with a normal text editor but I wouldnt fuck with it, personally.
It isnt even that hard to find, per game, either. Let's say you wanted to edit the clock speed on crash bandicoot. First, install the game. Now, unplug your usb from the classic and plug it into your pc. The file structure on your usb would go as such:
ROOT
Games
(Whatever number your game is installed inside of)
You will know at this point if this is or isnt the right folder because, though bleemsync shows your game by the name its serial is associated with, your bin and cue will retain the same name as it had before you installed it.
.pcsx
And heres where the pcsx.cfg lives.
Open this up in notepad++, change the clock speed setting, save, and plug your USB back in to the classic. Done and done.