skeleton functions and newline

[Harry Putnam]

Using the skeleton definition below as a model:

(define-skeleton hp-keywords
   "Insert nifty keywords string."
   nil
   "Keywords: " _ \n
   (format-time-string "%b %d %T %Y") \n
   "&&"  \n) 

I'm trying to write a similar one that inserts an editorial comment
and the date in specified format but doesn't insert a newline and
leaves the cursor one space after the date like this:
[HP -ed] Nov 26 04:48:06 2000 [] <==cursor

I want to be able to insert this into a line without inserting a newline.

(define-skeleton hp-date
   "Insert [HP -ed] comment and 
   date string with no newline."
   nil
   "[HP -ed] "
   (format-time-string "%b %d %T %Y")_)

I've removed all newline symbols and relocated the underscore to get
the result I want.  It works but if something else is on the line it
gets zapped onto the next line.

  Example:
  In this line below: 
  If i insert the skeleton here [] ..text.

Then "..text" gets zapped onto the next line.  I want the insertion to
just push it to the right without a newline.

To really enhance the versatility of the above skeleton I'd like to
add the ability to adjust the date in the same way the gnu `date`
command can be adjusted  like:

date -d "now -1 day"  to print yesterdays date.

Can this be done by incorporating the C-u prefix somehow?
I've imagined a command like:

C-u -1 M-x hp-date <RET> 

Or do I have to run it thru `tr -d"\012"' some how to remove the
trailing newline?