I have had a difficult time today re-reeding a small d drone. The drone was fitted with a metal bodied cane tongue reed that had started exhibiting some strange characteristics. I would play well and in tune and not show any sign of stopping for about 30 mins of playing then it would stop at even the lightest pressure and became very difficult to use. I didn't want to mess with the original reed so I decided to fit a new reed from my stock of working, all cane, reeds but none of them would play at the right pitch. They all played very flat some down to nearly G# but mostly around A. I couldn't get any of them to play at c (did I mention that this was a standard F set) I even took the working reed from my normal set and that was the same. When comparing the drones with my own set I realised that the problem drones were much longer than I make mine - the small d was 34mm longer, the big G was 48mm longer and the big D was 32mm longer but oddly the small g was 2mm shorter. In the end we, the owner and I, decided that the only solution in the short term was to use one of my reeds and play with the e tuning bead open. This solved the immediate problem and the drone sounded good and was no longer stopping.
Now, living in the south and insulated from the cut and thrust of traditional pipemaking, I wondered if there had been a move to longer drones. My normal sizes are very close to the sizes on the Cocks and Bryant book taken from the James Reid drawings. I know that the drawings are reasonably accurate as I have had the chance to compare the original parts used for the drawings to the actual printed sizes and the corelation is very good.
So my basic question is - is there a reason to increase the length of the drones?