Panasonic PK2 TV requires the power button to be held down for minimum time before powering up. I am unable to replicate this function in a VL1000 system macro. I have tried storing multiple power key presses but I suspect the delay between them is too long (TV rx led flashes in bursts). I know that the Timer key can be used on insert a delay in a macro but how can I remove the default delay between key presses that the VL1K puts in?
If I 'learn' the TV power key I still need to hold it down on the VL1K, which suggests that TV requires a repeated power key sequence rather than a special power-on message.

You will not be able to replicate the power on function for your tv on the VL1000. Any delay, no matter how short, between commands will be interpreted as a new command. Your last sentence tells the story, so you are stuck with manually turning on the tv, but it is more a constant sequence that is required than a repeated sequence.

Try using a numeric key to start the TV.

I taught my AV3000 all the number buttons for the Panasonic TV. It seems that in my case the key '4' was pressed for a longer time while learning so '4' is now sending a long lasting signal. This turns on the TV.

The 'Power' works well for turning off the TV though.