I think I'd rather someone cold cock me than put on aftershave right after a fresh shave
To me it's like sticking my face into a blowtorch. I rash up the day after shaving too, especially if I have to be outdoors, it's hot and especially if I sweat. It makes a huge difference what razor I used. I get whelps from an electric razor.
I find it's best to use the Mach 3, leave the shave cream (gel) on a little bit (like while brushing teeth) and hit the razor with hot water every few strokes. I also find less irritation shaving against the growth. These days I just keep a short beard trimmed with clippers and shape the edges and shave neck no more than a couple times a week.