There is no IDL in P6 or P7 unless you activate it using python (sorry, I don't have a link to the script) and it wouldn't utilise the optimisations that P8 with SR1 hasfor it in any case.

Even in P8, there are issues with creating ambient objects to light scenes. Fistly, IDL only 'sees' diffuse light, so you have to find the specular component using other techniques in order to have any kind of realism.
Secondly, in order for the ambient object to significantly light a scene you need to increase the value of the ambient material. If using the Alt diffuse channel for example you'd need to use a math node to multiply the effect. Using the ambient channel and using values higher than 1 is an easier solution.
But this introduces a new problem. In the example of the TV screen, ambient values greater than 1 will cause the screen image to render washed out - not realistic.
We might think to increase the sensitivity of the objects recieving the ambient light, but this will interfere with other ways in which IDL is working (i.e. the bounce light effect, the primary effect IDL was designed for).
I haven't been able to play for long enough to find solutions as yet, but I think it's important to remember that IDL wasn't initially intended (at least as far as I know with P8) to deal with 'glowing' objects, even though it can be made to do so.
That said, there may well be ways of balancing the way IDL deals with diffuse and ambient objects through use of materials and render settings. However, I suspect that more work probably needs doing on the way IDL works to have it properly working with ambient objects.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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