Looks like Burke will rely heavily on his roots of the gym shorts attacking philosophy. The "attacking" adjective may be deceiving to some as it does not refer at all to a heavy blitz scheme. In fact, it's the opposite as we'll stray from the zone blitzes that VJ used and the primary focus of the pass rush will be solely on the defensive line to get to the QB. Blitz packages will be minimal as that responsibility will be on the front four from wide pass sets (wide 9 alignment by the DE's). The LBs will read run first and react to the pass by then dropping into coverage. CBs will press and the safeties will be in Cover 2 with some Robber coverage (one safety rocks down underneath, the other rolls to the middle of the field) at times post-snap to provide a different look now and then. Simple assignments and the defense will rely heavily on execution instead of disguise and confusion. That's what he means he says he will streamline the defense.
Here are the drawbacks and weaknesses to that approach. Since the D-line's first job is to get to the QB, they can often leave creases and cutbacks for RB's if the don't react quick enough to the run. This can happen regardless if the LB's flow properly to their assigned gaps, especially with our front's wide alignment. With the LBs reading run first they are susceptible to the play action game be being sucked in and leaving space behind them. If we can't initially stop the run we'll have to use more Robber coverage for an 8th man (safety) in the box which will then remove press coverage b/c we don't have a true S2S Free Safety over top, putting us in more Cover 3 situations where they CBs will have to bail into a deep 1/3 zone. All in all, if/when a good offense can stall or nullify our execution we don't have much to rely on in terms of switching it up in favor of blitzing and confusion. It's a very straight forward scheme.
As far as cross training, I hope that it's simple camp/preseason process to feel out our new LB unit. It's good to cross train, happens often along units like the offensive line as well, but players need a spot to settle and get comfortable with. Not really a fan of not having a solidified leader at Mike to call the plays and line up the front 7.