OK, I see it.
An observation, which is probably somewhat unique to my practice, as I have my iPad at a height of 5' on a straight mic-stand with the inherent flexibility/instability. Taps on the screen can be inaccurate. Double-taps even more so. For me the introduction of the double-tap hasn't been beneficial.
Regarding the Document Toolbar; the arrows are obvious but what is the icon to the left of that and what does it do. The Cross and Check are greyed out. What is their purpose?