"Training, an easy topic. Becoming stronger is one thing when sparring, but the other is that sparring is only beneficial for those within the same class grade. There are still some limitations to sparring. Above a certain strength (levels), only the weaker side would benefit from sparring at a wide distance apart (the stronger of the two cannot exceed more than two to gain experience).
To a certain extent, those with a higher promotion in class grade three can no longer benefit from sparring. The same goes when the two spars were in the same class, grade three. Sparring does not prove any amount of experience (zero experience). Only true battles and battling against someone of the same strength in a life or death battle would provide a substantial amount of experience. For some, this is
