The land where the Magdalen Estate is currently situated was owned by Magdalen College Oxford and in the early c.20th it was planned to build Magdalen Park Estate as a Garden Suburb here.
The president of the college at the time, Sir Herbert Warren, had an architect brother, E P Warren, who was appointed to design the layout of the streets (a few of which carry the names of old Magdalen College presidents) and a significant proportion of the houses.
Frewen (note the difference in spelling but obviously the inspiration) and Routh were both presidents of Magdalen College and it looks like there was a little nepotism in the appointing of the architect.
By WWI houses between Garratt Lane and Swaby Road, and part between Lyford Road and Ellerton Road had been built but the scheme was essentially truncated when in the 1920s Wandsworth Council purchased the area between Swaby Road and Open View for the Openview Estate, and in the 1930s the area between Fieldview and Ellerton Road for the Fieldview Estate.
The Openview Estate was laid out with symmetrical groups of houses with Swaby Road Recreation Ground as a small rectangular of public open space. Two streets, Lidiard and Leckford Roads, run off at 45 degrees from the recreation ground providing longer roads than an orthodox street grid would.