@jon-nyc good points. The defiance of a subpoena is always a bad look, and promotes the "What are you hiding mentality," whether it be Bannon, Holder or Lerner.
Whoops. My bad...only one of them was held accountable.
But yeah, there's a place for - I hesitate to use the word - "secrecy" in government. Still when "oversight" doesn't get "oversight" is stinks. Behind closed (non-leaking - heh) doors, perhaps would be another solution.
The other problem is that these meetings usually end up being nothing more than political grandstanding, and little real knowledge is delivered, or even sought.