I think it was mentioned in "The Influential Factor" by Graham Lentz...

found this on the net:

http://www.bodley.ox.ac.uk/johnson/headings/mensclothing.pdf



The year 1912 proved to be the crucial period in the rebuilding of the Quadrant. Four years had passed since the completion of the hotel, but no more building had been started and within seven years all the existing leases would expire. In January 1912 Mr. Henry Tanner (son of Sir Henry Tanner), acting on behalf of Hope Brothers, the tenants of Nos. 84–88 (even) Regent Street, submitted designs for the rebuilding of the whole of the north side of the Quadrant between Glasshouse Street and Air Street. The principal innovations were the omission of the ground-storey arcade, the curtailment of the width of the stone piers and the alteration of the windows of the upper storeys. As surveyor to the Office of Woods John Murray recommended acceptance of the designs and in February they were submitted to Norman Shaw for his comments.

From: 'The rebuilding of Piccadilly Circus and the Regent Street Quadrant', Survey of London: volumes 31 and 32: St James Westminster, Part 2 (1963), pp. 85-100. URL: http://www.british-history.ac.uk/report.aspx?compid=41456  Date accessed: 16 April 2010.

http://www.british-history.ac.uk/report.aspx?compid=41456



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Not much information...