While it is questionable whether it was MacColl or Lloyd who introduced the hand-over-ear technique, one thing MacColl did introduce to the scene was the back-to-front chair.
One of his major things when running workshops was the importance of relaxation, and he argued for the necessity of being able to produce a clear flow of air to handle long lines and control tones.
His habit of sitting with the chair reversed worked for him, and for those of us who tried it out at home, but I don't remember anybody else ever using it publicly (Terry Whelan maybe?) because it had been so closely (and wrongly) identified as a MacColl affectation.
It is rumoured that some prat in one club who scrawled something on the back of his chair without his knowing - which says more about the clown who did it, (and those who find it funny) than it does MacColl
Jim Carroll