I haven't done too much studying of the Rocket, but I can answer the question of pressure/flow relatively quickly.
You have the general grasp of what most folks consider to "pressure profiling" or "flow profiling", but I contest that pressure and flow are so entangled in each other, that it's hardly a worthwhile discussion to hash out which is which. That said, here's the functional difference of approach with "traditional" pressure profilers such as the Rocket, and what Bianca is doing:
Pressure profilers utilizing a controller are monitoring the pressure (somewhere, could be pump discharge, could be puck, doesn't much matter) and adjusting pump speed until the pressure hits some target profile. Fancy machines can have a curve with various pressure targets throughout the shot that the controller follows by continually adjusting the pump speed. Complicated controllers, but simple idea.
Interestingly, these controllers are adjusting the flow of the pump and it is the puck itself that changes the pressure. Less flow through a puck means that it generates less back pressure, so even pressure profiling machines are adjusting flow to reach their goals...
Bianca and a select few others (Dalla Corte Mina, my own modified Rancilio S20 and to some extent, the "pre-brew" function of Slayer included) let the pump do it's thing and run at constant speed and put something that restricts the flow and is adjustable in between the pump and the puck. By doing this, the pressure at the inlet of the restrictor tends to be constant, as long as the pump is big enough to "outflow" the restrictor at its least restrictive settings (if you try to flow more than the pump can put out, the pressure falls, but this only happens during very fast preinfusion or flushing the group, so it's not too big a deal).
Much like pump-controlling pressure profilers, there's an 'interesting" part of the would-be flow profilers. The adjustable restrictor that is employed on these machines doesn't really profile the flow. What it actually does is create a pressure drop across it that varies the pressure hitting the puck, depending on the flow through it. More flow through the restrictor, more pressure drop, lower brew pressure. Less flow through the restrictor, less pressure drop and higher brew pressure. To give you an idea of the range, you can take Bianca's paddle at its lowest setting and flush the group with no basket. This represents a situation where the flow is high enough that there is no pressure at all in the group. Likewise, put a blind basket in the portafilter and you will see full brew pressure on the puck pressure gauge when the flow is zero. So, by adjusting grind and dose to achieve a range of flows, you can have any brew pressure you want without even adjusting the paddle, but in practice, you pick a grind and dose and then adjust the paddle to give you whatever brew pressure you desire by referencing the puck pressure gauge. Ironically, it is the pressure drop across the variable restrictor that results in the change in flow, so these "flow profilers" rely on changing pressure every bit as much as the "pressure profilers" rely on changing flow to do their thing.
One thing I can say about the so-called flow profiling machines is that their control schemes seem to be much more simple than the pressure profilers. The ones employing variable restrictors as described above I call "Variable Water Debit" machines. As they don't directly control anything. They set the stage for the puck and pump to do their respective things and it's up to the user to modulate the results. I'm a fan of this simple scheme because there's very little to go wrong, but it isn't as sexy as what the more fancy machines can do.
In my book, the only true pump-driven flow profiling machine on the market right now is the Decent DE1+ /De1 Pro machines. Lurking around the corner is the über expensive Duvall espresso machine, and it looks to be somewhat revolutionary in its design, but it's not available for purchase yet and makes a Slayer look "affordable" by contrast.