[RTTY] WHY put CQ at the end?

[Dave Hachadorian]

Several times during the WPX RTTY contest, I was called on my CQ frequency by stations who thought I was someone else, someone I had worked in the previous few minutes.  Apparently a RTTY Skimmer had misunderstood who was actually running on the frequency and who was the S&P station.  I can see how this could easily happen, because I was ending my CQ message, and also my TU message, with a CQ.  Here’s an example:
CQ WPX K7ZX KZ7X CQ 
W7WW W7WW 
W7WW 599 1025 1025 W7WW
599 945 945 
TU WK7S CQ
AA5AU AA5AU

So the skimmer hears
CQ W7WW W7WW and thinks W7WW is running, and spots him on my frequency.

Or, the skimmer hears
CQ AA5AU AA5AU and thinks AA5AU is running, and spots him on my frequency.

I know the skimmer guys have spent a lot of time working to reduce this error, but it is obviously still not perfect.

The larger question that occurs to me, is “Why do RTTY ops put a CQ at the end?”  Nobody does this in CW or phone contests.  Now that RTTY skimmers have come of age, putting CQ at the end is causing identification issues.  Maybe it’s time to stop?

Dave Hachadorian, K6LL
Yuma, AZ