[noggin]

If the difference is just reported subjective differences between different TVs displaying DV content and those two TVs are using different DV metadata routes - then I'd avoid any assumption of correlation meaning causation - the differences could be in DV performance and nothing to do with the metadata delivery system. It could just be that the Dolby result on some models is different to others. Unless someone is actually doing objective tests demonstrating a difference with DV test signals on a display that supports both metadata routes.

The difference being reported between "player -led" and "TV-led" Dolby Vision is likely due to profile limitations and encoding differences. Profile 5 if encoded with 12-bit PQ remapping is likely to look very similar to profile 7 "TV-led" rendering. If there is no remapping done, then profile 5 content is limited to 1000 nits.  

@wesk05 What does this mean for a UHD Blu-ray with Dolby Vision being played on a TV-led UHD Blu-ray player vs a Player-led UHD Blu-ray player? (Same dual stream source - but one using tunnelled metadata, the other using HDMI dynamic metadata?)