Not to be an ass, but that thread is from 2008. It's irrelevant when considering 2013 Flow.
True story. You have a good point there!
As far as loss of performance with a lack of toe cap, you actually get better performance. Instead of driving into the highback then down into the heelcup then the frame then the board, you drive into the highback, straight into the cable, staight into the base. Skipping a force redirection means more energy goes into the board. They're quicker edge to edge than traditional bindings.
As an engineer, I can tell you that the whole "better energy transfer" thing is simply a gimmick and is actually a load of crap. It was pretty obvious to me the moment I first saw it. Here's physically how:
When leaning back with a regular highback, force is applied to the back side of the binding and directly to the heel edge of the board, which pushes it downward. This is a 1st class lever with the effort force being the back of the binding, the fulcrum being the heel edge, and the resistance force simply being the weight of the other side of the board.
When leaning back with a Flow binding, force is still applied to the back of the binding, but instead of it pushing down on the heel edge, it pulls up the center of the board by pulling back the cable connecting to the center of the binding.This is a 3rd class lever, this time with the effort force being applied upward from the center of the board instead of downward directly on the back edge of the board.
The problem is that pulling backward from the center of the board actually requires more effort force than it would to simply push down on the back side. So yeah, you are transferring energy to the center of the board, but at the center of the board it can't be used as efficiently and could be considered wasted energy. Transferring energy straight the the back side of the board sends most of the energy in that direction and requires less effort force. So you're not "skipping a force redirection", you're actually adding one: 1.) pushing back to 2.) pull up. There is one-less force vector with a traditional highback: 1.) pushing back.
That's my theory of why Flow bindings are inefficient for making heel-side turns.