“6.8 On the present material, the only genuinely larger building for which there is meaningful rental information of any substance is 75 Bermondsey Street. The other larger buildings in the evidence are principally assessment evidence rather than rental evidence. In my opinion, that further supports the adoption of a tone-led methodology in this case. 6.9 To adopt the alternative route would, in my opinion, risk inviting the Tribunal to undertake, on incomplete material, the very exercise which the valuation officer could have pursued when the statutory machinery remained available. Unless the whole of the relevant evidential picture were before the Tribunal, including what other transactions were considered, what was excluded, and why, the Tribunal would effectively be asked to go behind the tone blind, without the information necessary to do so reliably. 6.10 I have therefore adopted what I consider to be the more reliable and proportionate approach, namely to begin with the best comparable assessment evidence, to identify the proper tone indicated by that evidence, and then to stand back and test that tone against such rental evidence as is genuinely comparable and useful only as a cross-check.”