Firstly, my mistake- I mislabeled the Omega "Cortina". The blue herringbone watch in the collage is also interesting- a Lemania Valjoux...well sort of. Its a Lemania branded watch that was made for the Football club FC Vallee De Joux in 1993- which is the script that you see. Here is a better shot.

This is the Omega "Cortina" from 1979, which I've included in an updated post and clarified this explanation.

So we have Omega using the design in 1979 when Lemania was still part of SIHH and then we have Lemania using the design again in 1993- before it was re-joined the Swatch Group. So I think that either Lemania designed the watch before it broke from SIHH, or perhaps Omega designed the watch and then sold it on to Lemania when the companies split. Either way, Lemania was not associated with Omega in 1993 when the "Valjoux" Cortina appeared.

Thanks for those additional Cortina/ Carrera photos- maybe "basically the same" is too strong.

Sadly, I'm not sure that the Heuer of 1983/4 cared too much about protecting the Carrera name. They'd already dropped it for the Gold 510.508, so I guess management at the time didn't value the name that much.

I agree that the Carrera is less clear-cut than the Cortina, but it still shows up as a Sinn (which as Chuck pointed out is very similar expect for the bezel), which to me points to a Lemania connection.

Thanks for your comments- detailed and precise as usual. I've made a few changes to the post to reflect the excellent points you raise- thanks

dc