I have never taught professionally and it has been thirty-five years since I was a pupil. I can share my feelings toward my lessons if it helps because they were mostly positive without being stupidly adulatory.
Thoughts in no particular order, both good and otherwise:
First and most importantly I always had complete confidence that he was able to DO things himself on the spot in front of me and not just talk about them. He could play classical, he could play jazz, he composed, he improvised, the list of his friends read like a who's who of early twentieth century music, he had worked professionally in Europe and the States.
Intimidating is definitely not the right word at all. I rather thought of him as an enormous, nurturing, encyclopaedic safety net; he could pick me up if I fell, so to speak. At no time did I ever feel frightened or in any way negative. I used to run the mile or so to his house eagerly anticipating playing him my ideas for the week and leave equally breathless, to try out his thoughts on the piano at home.
He always used one idea as a springboard for another. There was never any stasis, particularly in creative work. I was never permitted to feel I had reached the end of anything.
He praised me little, if at all. At his funeral, ten years later, I actually found he had been saying, to all and sundry, how good I was, which discovery was both puzzling and acutely embarrassing.
He didn't care much for propriety or formality. We had a few drunken lessons (him, not me). These were good because he forgot the time and they would extend into the night.
If he didn't praise, neither did he ever destructively criticise. If I did something wrong he would just say, "I think it might be better to do such and such.." and a demonstration would show what he meant quick and busy - more effective than a hundred "don'ts" and "mustn'ts".
He placed a very high value on the pupil's enjoyment of a wide field of music and would direct repertoire to this end. His eclecticism helped greatly. I would, say, learn a Chopin or Liszt study along with a Baroque piece, a Waller solo, something by Brubeck and a pile of improvisation and composition tasks.
He was completely honest and forthcoming about my raw abilities. At the first lesson he said such things as, "I hope you don't want to be a concert pianist – you need to be one out of the bag for that" and "Your ear's lousy but I can help you a bit with it" and "I think you have real music in you. I’m going to take you an entirely different way. I can help you get the music out. It'll take a long time - a very long time - but you are one of those who will get it eventually, I can promise you that."
And I did. Later rather than sooner I’m afraid but the point is that all cards were on the table and he was correct. No false hopes, no disillusionment, but a very positive course to steer. A pupil can respect that right away.
He was also honest about his own few musical limitations. He was dreadful at classical ragtime despite being a professional jazz pianist. All the notes were there but the life was not. “You have one over me there, Ted”, he would say. Again, respect comes easily when a teacher can say things like that.
He had many pupils, of which one or two have become professors and concert pianists and a few have become professionals in other genres. I became nothing in particular – just someone who improvises, composes and creates flat out and enjoys every minute of it.
Which brings me, in retrospect, to his most remarkable ability - that of recognizing, tolerating and developing unorthodoxy and originality in pupils and discerning those cases where it should be left alone. That was and, I am sure still is, a very rare thing in a teacher.