This will be the actual issue for the courts (and ultimately SCOTUS) to decide, the specific device is just a pretext. Hopefully the judicial branch will recognize how this can essentially cut off both itself and the legislative branch from any real control.
Not a lot of hope on that front, as they've already demonstrated a willingness to abandon their duties: administrative subpoenas, tens of thousands, issued by federal law enforcement agencies - not courts.
So it is much closer to "meh, do whatever you please..." but more accurately it would be:
Executive branch: "Yeehaa! Get outta mah way checks and balances, we got bad guys to string up and no time for robe wearing slowpokes!"
Legislative branch: "Sounds like a great idea, white hats can do no wrong."
Judicial branch: "...blank stare...shrug".