TV Modulator Advice

This article indicates that combining modulators and digital cable may be complicated:
Hometoys article on digital cable and modulators
You probably need to split the cable into digital-only and analog-only runs.

By the way, in case people aren't aware of it, most (if not all) of the inexpensive modulators are mono only. They may have stereo inputs, but the modulated signal is mono.
I had no idea it became that complicated when digital cable is involved. ;) I may have to re-think my setup if I run into problems...
Digital cable is the only reason I haven't implemented this yet, but last time I looked into this was over a year ago, I was hoping there was an affordable (and working) solution by now.
I have seen "digital" high-bandwidth splitter/combiners at the hardware store recently. These also claim to pass DC. Any reason to think that these would not do the job?