My take on the inner beast is its kind of like the Hulk. Its a released and unrestrained embodiment of your desires. The lvl 50 - 60 quest deals with why the WoL tames the Inner Beast effortlessly and the two brothers have failed but basically it isn't the echo.

Since its part of the story:
The secret of the WoL in taming the Inner beast is their core desire. The WoL is strongly driven to be stronger to protect others. Their inner beast acts like a mother bear raging against those who would harm its charges. Curious Gorge and his brother on the other hand are driven by the desire to be true warriors and make their art known by all. It is by harnessing his desire to protect his comrades in battle that Curious Gorge is able to finally tame his inner beast.

Its worth noting they are now training Mealstrom soldiers in the Warrior arts now. Combined with the fact that there are Marauder guild members training in the arts of the Nymian Royal Marines and their tactical skill, the Mealstrom is looking at a potential increase in its military prowess and strength.