When we go to my wife's son's house then the main road that goes to it is 20mph
mostly due, I assume, to the row of shops about half way along and associated refuges and stuff in the road
so if I come across a bike in front of me then if there is not really much point in trying to pass them as
a) I can;t go that much faster then them anyway
b) if there is no traffic coming the otehr way then the chances are that I would come across some road furniture anyway
In addition, any traffic coming the other way may well be doing 30ish so judging how to pass gets even more difficult
adding all that together there is no point in passing
except that it appear that not everyone agrees with me
so if that does happen I often get someone driving up close behind me
or coming up behind at 30ish and then suddenly realising that I am going at a slower speed and braking suddenly when they get too close
One guy even over took by going round me, the bike AND a traffic island in order to get ahead
naturally I was right behind him at the pelican crossing just up the road
and the bike went in front of him
(I'm assuming "him" but I didn;t look - but I reckon that's a safe bet!)
and on top of all that - a lot fo the time we are on that road it is just after the kids get out of school so the older kids are drifting homewards
hence kids in uniform crossing roads is quite common
but still it happens!