To try an rephrase, I should first give a little background. In my old house, I put in an insteon lighting control network. Hardware reliability made me question its use in my new house and my structured wiring guy suggested HAI. So I got the OPII installed and have just started adding the HAI lighting as I have time and money.
I was used to Powerhome for controlling the UPB insteon stuff. Steep learning curve, but then it was easy to create links between the switches. Controller, Responder, the switches talked to each other and were fairly responsive... minimal delay.
Now with HAI I'm trying to use HLC mode (perhaps that's my problem to begin with), organizing by Rooms and devices within the room. Linking 2 switches to mirror each other was so easy in powerhome, but I can't seem to find the equivalent in HLC.
Right now, when I press the slave switch on, the OPII reads the press, then finds the code that says when this happens, turn on the master switch too. Then another block of code to turn it off when pressed off. Then 2 more code blocks for the master switch to keep the status LED in the slave correct. This seems like I'm over complicating the issue.
So I'm thinking there has to be a reason for the yellow "control" wire on each of the multi-way switches. Some way for the switches to talk directly between themselves and bypass the OPII.
You're right that I do need to just go buy another PIM and cable.