While true that an old rusty wobbly-headed crooked hammer is the best tool for the job if it's right next to you and you only need to pound in a couple of nails, we are talking about programming web applications here.
In that case, I always use good tools because typing in a few lines of Perl or Lisp is just as easy as typing in a few lines of PHP. Easier, usually.
Isn't it always just a couple more nails, here and there, till the next feature's ready to go?
An old rusty wobbly-headed crooked hammer is the best tool for the job if it's right next to you and you only need to pound in a couple of nails.