In a single speed drive train the master link is locked on until you pry the spring clip open

whenever you press out the riveted pin head you stretch the hole in the side plate .. it wont stretch back

But as you are not flexing the chain to shift sidewyas and the Pins are much wider than the outer surface of the Chain

the likely hood that the pin will fall out is reduced ..

I've been running a 3/32 old Bushing type chain on my Rohloff Bike . I could just press the pin back in to close the loop

1/2 link is just a z bent side plate width of inner link on one end and outer link on the other..

I put one in just to open the chain, for Bucket cleaning, in the same spot .



I used 3 Masterlinks on my Chain whips [ to pull apart multi speed freewheels ]

the chains on the whip dont come apart [they used to] I have cheater pipe handles on them .

what do you mean by jams ?

really expensive chain tools for thin derailleur chains try peening the pin head wider..

you dont re heat heat treated steel unless you want it Soft.