cron.allow, cron.deny: what's the big deal?

[Dan_Jacobson at ATT.COM]

So what's the big security increase gained by having to ask root to
let you use crontab?  The only cron related problem I can see is
forgetting to remove a user's crontab and at(1) jobs when her/his
account is deleted, e.g., at the end of the semester.  Am I just dim?
-- 
Dan_Jacobson at ATT.COM  Naperville IL USA  +1 708 979 6364