In a recent post, Kardafol stated,
"Also, don't leave out brackets, as it slows the script down as mIRC will have to place them itself ..."

I do not doubt you whatsoever. I would like to see what other people say about this. I would like to verify this information as this is rather integral I feel. A script full of missing brackets would be extremely slower than one that wasnt missing any. (Not talking bracket mismatch, you know what I mean.)

Some points from the help file:
If-then-else section:
Using brackets speeds up processing. If an alias uses too few brackets then the statement might be ambiguous and the alias will take longer to parse, might be parsed incorrectly, or might not be parsed at all.

From Aliases section:
the command prefix is really only needed when entering a command on the command line. In scripts, all lines are assumed to start with a command, so you don't need to use the / command prefix.