Slightly returning to the topic perhaps, how do others see the situation where there are three 8' Great diapasons but only one 4' principal? I have no assistant organist, but our newish asst priest plays the organ and does occasional hymns and postludes. Recently I came across him practising a Bach Prelude and Fugue, using a diapason chorus (8, 4, 2, Mix) but based only on the open no 3. Breaking into a cold sweat I hurried out of the building for a strong drink and a breath of fresh air after this damage to my ears. Later, when no-one was around (!) I experimented with this apparent flimsy impersonation of a 1922 Willis. Seriously, however, it did not sound too bad close up (it's an attached console) but was a bit thinnish in the building, despite Sw to mixture being coupled. The 4' seems too big for the OD 3 - but I do not like the combination of the claribel 8 to pad it out, nor using the 4' Flute Ouverte as a perky 4' above the OD 3. So is the OD 3 never intended to support Principal 4' Fifteenth 2 etc? Did Willis intend it more as a quasi viola solo stop, or is it simply a matter of 'use your ears ' (fair enough advice) or would a builder like Willis have specifically set the principal 4' only to be part of a chorus using either (both) of OD 1 or OD 2?