Li Fan found that Master Xue was right; cultivating an avatar really did consume time. Even though he could operate two accounts at the same time and the Taishu skill did not compete much with his body's cultivation resources, it still required significant energy to replan the cultivation path for his Daoist body.
For instance, when Li Fan had devoured five Nascent Soul stage monsters, intending to digest their demonic cores and cultivate the "Qingyang Dahua Divine Skill," he suddenly realized that this Qiongqi avatar had a fatal weakness—it did not possess a proper Taiji Realm physical vessel.