Two guys arguing about the new vs. the old flute:
De Lorenzo vs. "Smith" (1904)

The following appears in a short biography, by William E. Hullinger, of Leonardo de Lorenzo that appeared in The Flutist of 1922. It purports to be a description of a conversation between De Lorenzo and another flutist regarding the difficulty of certain passages, comparing the old flute and the Boehm flute. This excerpt was reprinted in De Lorenzo's My Complete Story of the Flute (1951).

In 1904 De Lorenzo had a very interesting controversy with a fine gentleman, whom we will call Smith, of between 50 and 60, and an excellent flute-player. Smith had studied the old system flute all his life and, having recently unsuccessfully tried to change to the Boehm flute, had become its most stubborn enemy, whereas De Lorenzo who had made the change only a year or so before, was tremendously enthusiastic about it. Smith, who was twice De Lorenzo's age, was a bit over-confident of his knowledge of both systems, forgetting that his younger colleague had also extensive knowledge of the possibilities and short-comings of the Ziegler flute, as the old player used to call his Meyer system. The following conversation took place:

Smith: This cannot be done without that ridiculous shifting of the thumb.
De Lorenzo: What difference can that make as long as one is able to play it fine and clean? (And he played it with considerable ease.) You must confess that the arpeggio in the dominant seventh in E-flat, which is so simple on the new flute, is almost impossible except for a virtuoso who is equipped with an instrument like yours, with an extra G-sharp key.
Smith: It makes no difference how many keys one may have, but it can be done beautifully (playing it really fine and clean). That high F-sharp on the Boehm flute is enough to discourage anyone with a good ear, especially so if one uses the middle finger for an easy change of fingering.
De Lorenzo: Not necessarily. All F-sharps with the middle finger must be avoided except in very rapid passages when it is followed or preceded by an E. The high F-sharp, when written pp., can be produced with great ease and beautifully in tune if one places his right hand little finger on the C-sharp key.
Smith: But you cannot shift the little finger on each high F-sharp in the noted passage from William Tell.
De Lorenzo: Play the whole passage with the right hand little finger on the C-sharp key. (Passage played.) Besides, the Brossa F-sharp lever, which can be placed just near the fourth finger of the right hand without shifting the trill keys, is very valuable if one desires it on his flute.
Smith: You are a hard worker and a very ambitious young man, but I am more than convinced that the old Ziegler flute is superior to the new, as I have here (producing from his pocket) a phenomenal passage for you which I know is a stumbling block for the Boehm flute.
De Lorenzo (who at a glance saw what he was up against): Yes, that passage is tremendously difficult, but with patience and hard work the intelligent player will be able to master it by using the harmonic position on the high G-flat and shifting the thumb when necessary. I see that you are well acquainted with the Boehm flute and it really surprises me that you did not stick to it.
Smith: The high B-flat on the Boehm flute is flat when played pp in the original position and sharp if one uses the first trill key (D-sharp).
De Lorenzo: The master of his instrument will always find means of adjusting those little inevitable defects which are a characteristic of all wind instruments. The following position for high B-flat may be used only in the p and sustained note: left hand, first and third finger closed, upper trill key open.
In regard to trills, the Boehm flute is simply wonderful when one thinks that the following, which are impossible on the old flute are, comparatively speaking, easy on the Boehm flute.

In spite of the animated argument, Smith and De Lorenzo parted the best of friends.