The whale and Stitches were the only ones who could tell how well the procedure was coming along. But the whale was preoccupied with the pain of the trees burrowing into its wounds and couldn't determine whether it was going well or not.
Stitches, on the other hand, was surprised at the ease with which the trees had gotten acclimated to the situation. Stitches only needed to coax the trees into absorbing the mana at the beginning. After that, Stitches worked hard to control the trees' advance and foster a symbiotic relationship between the whale's body and the trees.
