I guess it would be when it is out of the Pokeball. Also, there is a book, with the words war and peace in it, that are highlighted.
It all depends on how leveling works in your RP. If Pokemon gain XP for using their abilities and such outside of battle, then yes(except for maybe Charmander...he just used Dragon Pulse once. Maybe he should stay where he is. Spinarak is a versatile beast though and will take Mean Look.) This would allow Pokemon to gain levels quicker and prevents this from becoming and RP of level grinding. So many of the fire types can make camp fires, the only water-type currently on the team can be used as an emergency fire extinguisher, the various electric types can be used to power various electronic devices, etc.
But where is the book on the table or on the bookshelf?
^ See what I mean?
Also, PM of ideas coming your way to think about.