The fence concept is a good one, and logical.

But keeping a fence in every day life is not as easy as some might think, but regardless you made some decent points I just wanted to get that ''off my chest'' so to speak, since there seem to be a lot of people who advocate awareness & avoidance so much that it seems the most important things keep getting forgotten or they go no further than just being fancy catch phrases for some in MA.

Culture also comes to play here a lot... In a lot of countries what I or You might consider as ''invading my personal space'' is completely normal and actually expected.