Within a foot? not that often.
Closer than I'm comfortable with? more often than I'd like. don't know if it's too close or I just need to get more comfortable. Never been brushed, been honked at a lot by idiots who have a clear lane to pass me but would prefer to harass me from behind instead, but no contact ever.
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Bikes: 1996 Eddy Merckx Titanium EX, 1989/90 Colnago Super(issimo?) Piu(?), 1990 Concorde Aquila(hit by car while riding), others in build queue "when I get the time"