There are several signs that it isn't. The latest important sign is that Bruce Ohr testified under oath that he has NOT been questioned by either Mueller or Huber. This means that Ohr is either so deeply involved that he will be one of the first to fry, or conversely, that his involvement has gone unnoticed. The latter meaning that the investigation is quite superficial.
Another important fact is the involvement of Rosenstein. By all measurements, he is an important member of the Obama corruption cabal. Yet he is clearly directly involved in leading stonewalling the release of important evidence, and in directing important personnel. It's difficult to see how an investigation of corruption could proceed properly with him blocking the paths.
Nevertheless, your proposal seems quite possible. Sessions is not a fool. His important work in other areas of the DOJ is quite impressive. It is important to leave no stone unturned if the DOJ is to prove guilt at the upper levels of the Obama administration. While not fun to watch, the current investigation against president Trump is absolute proof that no one is exempt from investigation, and so will be good evidence that similar investigations against Obama and Hillary should not be dismissed as simply politically motivated attacks.
Sessions’ work requires the skills of a surgeon with all of the deep state lifers infesting the DOJ. Think of it as a cancer needing a multi-prong approach to remove the malignant spread.
The “bad” signs you list certainly do put a damper on hopes of Sessions heading a “silent execution” of the corruption in the FBI and DOJ.
Yet, maybe it is possible that while Ohr didn’t lie about not being questioned by Mueller or Huber, he withheld info about being questioned by people closely connected to them.
Would help to have transcripts of the Congressional hearing to know for sure, but seems to me that if Sessions is being “stealthy”, he would NOT want ANY of the “Trump” cards he holds to be laid on the table just yet.
Afterall, the stakes in this “game” are so high, and the deck so clearly stacked against him, that acting “sleepy” might be the only way to turn the tables on those who have undermined our Republic with their corruption!