.TP file support?

[sub]

I guess I thought that all transport streams had timing data inserted.

All transport streams do include timing data, but this mainly limited to the audio/video sync, and not really designed for the purpose of skipping in recordings. Things like changes in timeline, or wrapping, or discontinuities can cause major issues with knowing how long a recording is during playback, and where to skip to in a file for a specific playback time. NPVR captures some additional information while recording so that it doesnt have to try to guess this stuff, allowing for really accurate skipping.