Serious/committed buyers look online.
Seriously? There are people without internet, or access too it when absolutely necessary? Do you think the buyer will turn up in a FJ Holden with a boot load of pounds and shillings?
I guess one of the drivers for us is that I know a buyer, looking right now, who is aged about 60, who uses the paper. She has no internet, no mobile phone. She will buy a house from the newspaper.
She is unusual, yes, but she is a buyer.
I browse the local paper and the Courier Fail, but I'm looking at 'trophy' style houses with full pages. I skip the tiny little ads. The odd one works. I'm very happy with my home, but for instance that converted water tower (I think you posted it here) that sold recently really caught my eye.
The CM's been running ads saying print as well as online get's something like 5% more than just online. I question the 'research', but perhaps they're right.