Wobbly riding...Generally, it is due to arms being too stiff (locked arms) and / or too much input from the handlebar. Also, looking down versus looking ahead while going more slowly can cause wobble. Also, juniors tend to wobble.

As a trackie, I ride rollers a lot - warmup, cool down, high cadence and etc. In general, rollers, without an added resistance feature, are too easy for longer, lower cadence, harder efforts.

I like it when my competitors do not use rollers and encourage that behavior.