The addition of walkways on Tower Bridge (NCE 9/16 August), was not an operational flaw as stated but stemmed from an adaptation of Horace Jones' 1878 design by John Wolfe Barry.
The width between the main towers was reduced from 92m to 61.2m, with the central arch being replaced by horizontal girders, thus reducing the risk of tall ships striking the bridge if they were not in the centre of the channel. It was a relatively simple task to provide for pedestrians within the horizontal girders, albeit with additional lifts and stairs.
You also state that the mock Gothic architecture and Portland Stone cladding was 'insisted upon by the authorities'. However, there were no town planners, heritage societies or conservationists in Victorian England.
In fact, the design selected by the Corporation of London in 1884, was still significantly different from the bridge as built. Jones' design envisaged significant architectural detailing finished in red bricks, but he died suddenly in May 1887, 13 months into construction.
His assistant, George Stevenson, reputedly insisted on major changes in the architectural appearance of the bridge before accepting the commission. The choice of stone facing and simpler detailing is what we see today.
Roy Aylott OBE (F) St Albans, Hertfordshire