A nice try at observing the path of the electron to see which side of the slit it goes through (I gather? - chamber before, vacuum, slit vacuum, chamber after) but this is not accurate enough for this purpose and you would have to have some way of getting an accuarate velocity of the electron at the double slit point.
The real problem is not finding a way to perform a which way experiment, this has already been done by Afshar (www.irims.org/quant-ph/030503/
- see also New Scientist article July 24 2004 issue).
The problem is that the QM formalism's ontological duplicity makes it almost impossible to get a clear interpretation.
The interpretation from a real physical perspective is clear!
But QM allows for non-physical perspectives such as TI, MWI, Copenhagen. Once one takes any one of these perspectives which remove physicality and locality to the photon or electron particle (i.e no longer a localized particle with a localized radius and a real path in space and time, but a mathematical spread out over space wavelike emorphous entitiy with whatever properties one choses like the ability to be both dead and alive at the same time), they all can accomodate themselves to any experiment.