The game will read the files in either text of binary, but binary is smaller so the game performs a little bit better with it. But then of course it is impossible to make any changes in your mod. So while you are changing a mod you need it in text format, but if you're just playing it and you think it is as good as it is going to get, its probably better to change it to binary. That said often times I change random things at random times with my mods as I get ideas while playing (so I leave them in text), but thats just me.

the thing is, if you keep converting it back and forth from binary to text, I think the converstion program sometimes loses are character or two, which can cause major crashes in the mod