I don't recall seeing any 05R landings during the various spells I had working in the CTA in the mid-70s, so they certainly weren't as common as those on 23L. That's hardly surprising given the relative frequency of strong NE vs SW winds in this part of the world.
Interestingly, the extract below from a July 1968 Aerad chart shows 15R/33L as having recently closed (for the construction of T3 Pier 7 for the 747), but 05L/23R still available. At that point, the latter would have been by far the shortest (and narrowest) of Heathrow's runways (6255' x 250') and I don't think it survived much longer, as by then it was constraining any extension of T3 Pier 5. The current control tower also stands on the old 05L/23R footprint.
