Robert Comsol wrote:
Warp capability was a retcon concept and frankly I'm wondering if that was a TOS requirement when I actually look at Gideon or Ardana.
* snip *
OTOH I could imagine both planets having invented satellite technology or the like enabling them to detect warp drive travel of others, which IMHO would equally justify a first contact encounter.
This is how I tend think about it.
Particularly since it seems like if the galaxy were as crowded as Star Trek's seems to be, any civilization reaching an early-to-mid 21st century level of development should be capable of detection of all kinds of transmissions showing life on other planets.