The best way to ensure table saw safety is to keep a certain sector of people well away from any machinery, these are the ones who need protecting not from machinery but from themselves.
This has been discussed on many occasions and the first point to note is that a table saw is not a portable tool so it cannot inflict injury unless you place yourself in harms way unlike say a 9 inch grinder or chainsaw. Safety has to always start with the person, forget machinery guards because if they are not in place then it is still safe because you as the person simply do not use that machine. I would suggest that the only way this saw stop system would be effective is if it is fitted to every table saw manufactured so no mater what machine you use it has the feature otherwise people with the system become complacent, part of safety is feeling that this machine is dangerous and treating it with respect.
Think of why accidents happen in the first place, there is often a simple cause. Crowded workspace, trip hazzards, poor lighting, no training, wrong attitude to safety or just bad operational practice so remove these and use long push sticks then how do you get injured ? Well not using long enough push sticks or being in a rush are good examples.
Then the sawstop itself, still not convinced because having worked with high integrity safety systems then a key part of these is testing to confirm that you know that upon demand this safety system will prevent the hazzard from being realised. So this sawstop that is preventing it from causing harm must be failsafe, ie if the safety system is not working then it must prevent the saw from working so how is this achieved. Also just like E stops and RCD's you need a periodic test to confirm operation, can this be done ?
