: Tone production, bowing styles (spiccato, martelé, ricochet), and string crossing.
Although the exercises are grouped, the protocol often suggests interleaving. For instance, after completing a bow‑control exercise, the next cycle may involve a left‑hand agility task, deliberately to enhance discrimination and reduce contextual interference . Research shows that such interleaving leads to more robust retention than blocked practice. simon fischer practice 250 pdf