When it comes to rote technical exercises, is there any information on whether or not any of the following produces better results than the other:
a) Pick one exercise and focus on getting it up to a goal speed, then move on to the next one. For example, work on Exercise A until it can be played cleanly at 240 bpm, then do the same for Exercise B
b) Work a group of exercises at once in incremental steps. For example, Work on Exercise A and B until both are at 190 bpm, then get them both up to 195, and so on until the goal is reached.