Naah its never silly to have 3 central midfield...
depends on the arrangement you have...
you can have it flat.. or a trio, with two on defense and one on attack, or the other way around,.,.

possession wise, the three midfielders must always be positioned to intercept passes...
what i mean is you cant have a fixed position mc...
you may need to re position them possibly 70% of times for every new match...

if done right, then it can do more damage to the opponent...
the right support for the 3 strikers or wingers would mean to a high scoreline...
and the fact that a CM has a duo role where they attack and defend gives us a clear idea that they play a part in defense too...
possibly a better play build up...