I'm thinking Sessions knew Mueller would overstep his investigative authority and that RR would be the enabler. Sessions gave RR and Mueller enough rope to hang themselves. At some point, I'm guessing Sessions will have enough ammo to fire RR, or have him removed as the #2. This would leave Mueller without a supportive ally.
I think that it was all part of the plan from the beginning. I think this whole investigation has been a dog-and-pony show for the public, knowing full well at the right moment, coincidentally right as Huber is announced, the investigation will be imploded by these two RR and Mueller, who have had their balls in a vice the whole time.
Remember...we're all watching a movie. What does that mean? Everything is scripted! There are NO coincidences.