The way it reads to me, keeping the VV in your toolkit is intended to reduce the action economy aspect from 3 actions (draw > quick alchemy > use) down to 2 actions (draw from toolkit + quick alchemy > use).
This way you can spend 2 actions doing your alchemy business and still have 1 left over to stride or do whatever for the majority of your playtime.
Quick Bomber further compresses that down to 1 action for specific actions.
