This proposal sounds good -- in some ways, simpler than the microtome procedure. But the machines would probably have trouble with the sheer size of neurons and their connections. A neuron may have inputs many millimeters away, and may have outputs connections as long as a meter. How could a tiny machine (smaller than a cell) monitor all those inputs, or reach all those output sites? It would have to be capable of growing as large as the neuron itself, and in the same shape. Proponents of nanotechnology sometimes claim that almost anything is possible. Let's suffice to say that it's not clear how this would be accomplished, for now at least.