I was thinking that GDT should have a short loop tool. It would work like a variable time loop that would quickly isolate a short passage and repeat it. For example the cursor could represent a magnifying lens and when placed over a certain area in the waveform, it would loop that area to a setable short duration time such as maybe a half second or so. The idea would be great for getting that really difficult note or short passage to repeat without spending the time setting loop points.
When the mouse is moved, the loop will change accordingly on the fly.