SOPP657: I hear from respected organists that these trio sonatas are some of the most difficult music to play, and you executed it perfectly!

This question was sent by John, and he writes,

Dear Vidas, wow this is so beautiful! I hear from respected organists that these trio sonatas are some of the most difficult music to play, and you executed it perfectly!  Thank you for such an enjoyable experience, and also for setting such a great example for me, your student!
Take care, John