Seems to be the case. Training Goji-chan to tap into her real power without going overboard.
It's more in the lines of 'realizing your true potential'. Friends is essentially humanized animals with supernatural powers and abilities derived from their animal characteristic, so humanlike some of them forgot that they're animals first, human-like being second.
For this training however, it's done to judge Goji-chan's original size and body mass: she did exhibit strange sudden weight gain characteristic of large animals when burning down the Cerulean.
What Blue Whale added in the end, that 'being in the state of Wild Release makes it easier for you to unleash your power' is that Wild Release both activates their Sandstar and making their characteristic revert that of their original animals', in Goji's case, adding to her mass.
*Drizzling*The result shall be like this.When one is first learning, it is easier to exert one's force of will when in the state of wild release, you see.Ohhh