What you and Tod are forgetting is that the Replay is a PVR and has the entire show on the hard disk. It can detect both potential "in" and "out" points of each commercial break.

The VCR is a VCR and has the entire show on a mile of plastic. It can detect both potential "in" and "out" points of each commercial break...

Seriously, The VCR ones (at least RCA's) work by going back later and adding the in/out point markers to the tape. I don't know if it's deciding where they should be while it's recording the first time and just marking them later, or deciding where they should go after the recording's over, but either way it has the same opportunity to analyze.

Considering that VCRs have done it for many years, and they still have the same dinky chips in them with 64 bytes of memory to store your 8 programs, I think it's amazing the VCR ones work at all.