Clearance on hold, hold for release

I've only ever heard "hold for release" at non-towered airports when
using an RCO or when working via FSS. Then, it's part of the clearance
and needs to be read back. At a towered airport, I don't see the point
in him telling you "hold for release" as ATC has to clear you on to
the runway in any case. I've some times been told "Hold short --
awaiting IFR release" when I've called #1 and ready to go at a towered
airport, but that's really just a hold short instruction with a reason
attached, and even then, it's not like your situation where you were
given the hold pretaxi.

Further to this, I found this in the ATC manual...

http://www.faa.gov/airports_airtraff...atc0403.html.1

"Hold for release" instructions shall be used
when necessary to inform a pilot or a controller
that a departure clearance is not valid until
additional instructions are received.

While it's grouped together with void times and other techniques used
at non-towered airports, there's nothing in there at explicitly says
it can't be used to indicate an incomplete clearance at a towered
field. Still it's awfully misleading. "I'll get back to you with the
beacon code" would have been a lot clearer!