Short answer is no. (i hate saying that since someone always proves me wrong)
You cant replace the words as such (you cant edit the EXE anymore) , but you could make a custoim aliases, that then hides the originial text. (this isnt a perfect solution of course)
Using your 1st example....
alias ignore {
if ($show) {
..heres the problem you got to sort out what it should say manually and echo it here, pretty hard eh!..
}
!.ignore $1-
}
However this wont work for timers since the timer command can have the timer name added to it /timer or /timerx you cant alias em all!