Scott, you're right that 'descend now' isn't correct phraseology, but, hey, if it works...
Out of interest, do you ever have problems with the term 'maintain'? If you clear an aircraft to a level without using that word, what will he do when he gets there?
In the UK, maintain is generally used to advise a pilot not to expect continuous climb, and caution therefore is used when talking to American pilots.
Hope things are sweet in Tx!
