Rule No# 1 with S&W is there are pretty much no rules with S&W...Well , none that weren't broken or bent at one point or another.
What makes your 586 interesting is that its an early 80's gun not only with a pinned blade but with two set pins which is just not seen on any other S&W I can recall,
This pic is of a nickel Model 19 with "Proud" front site ramp pins but notice they hold the ramp to the barrel rib not the blade to the ramp .
the Model 19 pinned ramp changes in late 1969 during the dash 3 revision, After that the ramp becomes part of the barrel (perhaps why no Model 66's are found with pinned ramps being introduced in 1970)....Early 1970's Model 19-3's then have a single pin that holds the front site blade to an integral ramp that is polished flush (not sure how long that practice lasted).
Years later we see S&W's with a single pin holding the front site blade to an integral ramp which aids in changing out the front site considerably but again they are held by one single set pin.
Might be worth a factory letter if you would like to confirm how your gun shipped, maybe another member has one like it and can post pics,
Interesting if confirmed as a factory upgrade since their past and present method is a single set pin on the FS blade.
Neat gun