Greetings, as usual.
Concerning the Tuck Front Lever Pull-up, as presented in Building the Olympic Body (Dragon Door article), the accompanying photograph shows the knees of the trainee bent to his chest, at the pinnacle of ascension to the bar, thus presenting the knees as an obstacle between his torso and the bar itself.

That is, although the movement begins in the Advanced Tuck Front Lever position, with a flat back, it finishes in the standard Tuck Front Lever attitude, as the name suggests.
Is it not possible to maintain the Advanced Tuck Front Lever position throughout the movement, such that the knees do not stand as an impediment to the trunk making contact with the bar? Granted, the level of difficulty would increase, and the name of the exercise would, in such case, have to change. ![]()
Cheers,
Andrew