Using 2 tiu's and 1 remote

Yep, that's called Super-TIU mode.  The question is, do you really need two TIU's?

John you just peaked my curiosity. I have 2 TIU's running in supper mode and did it so I could control the trackage loop extensions on the far side of the table. (50 " away). I only have one loop running over from the main table and thought with all the engines, Passenger trains and extra loop extensions over there it was easier and better to use another TIU.  Am I Wrong in thinking this?

You have four channels for the TIU, each channel will handle 10 amps.   Each channel will drive at least 100-150 feet of track, depending on specific track condition and the number of joints.  If you've used all four channels of the first TIU, then it makes sense to add another one.  However, using #12 wire, you can easily pipe the power over to the other side of the table if that's the only limitation.  Worst case for a 50 foot run of a #12 wire pair, you lose 1.6 volts at 10 amps.  In truth, you probably aren't actually drawing anything close to 10 amps all the time, so the drop would be considerably less.

Thanks John. Answered my question. I was Correct in adding another TIU not only for reasons you stated but all 4 channels are used on both! Running lashups of 4 engines on extended passenger trains does draw a lot of amps as according to the Z4000.

Well, the TIU handles a MAX of 10 amps per channel, and you can't parallel channels.  So, I don't think the current draw changes the picture unless I'm missing something.