1. I've never seen vintage woodworking vises come with wood on/for the static jaw. 2. There are only two holes on the static jaw, unlike four on the dynamic jaw. 3. The two holes on the static jaw are tapered for a screw to fit below the jaw face.
I applaud your persistent skepticism. People all too easily believe something just because someone said so. Perhaps we can draw a response from someone more expert than I. In the meantime, I have some reasoning to offer.
#3 When I got my first one, my dad had repainted it as a gift. I was so convinced by the countersunk holes in the static that he had put it together wrong, that I backed out the rods with a pipewrench and assembed them on the other side. Of course, there is then no way to mount or use it in that configuration.
#2 I think the countersinks are there merely to guide the screwtips through the static without demanding precise tolerance. If, as at first seems reasonable, the countersinks were in the back of the static, you wouldn’t question their purpose to hold the wood pad, BUT you would have to add the pad before attaching the vise to the bench, making it awkward to replace. If the manufacturer simply did not countersink the holes at all, you would think they weren’t finished to match the dynamic. I think it is possible the countersinks are cast in simply to standardize where the holes are drilled subsequently in the manufacturing process.
The real mystery is, why are there
more than 2 holes in the dynamic? The only function of screwing wood pads to the jaws is to prevent them from falling on the floor when you take the workpiece out of the vise. How do I know? Because I
don’t have pads screwed into mine. I just put any convenient scrap in there when I want to avoid marring the workpiece. As a compromise, you could make or buy magnet-backed pads.
#1 You are wrong about not seeing it done if you saw the pic I eventually posted to our previous confab. It’s of my friend’s father’s vise (not mine). It hasn’t been touched in at least 25 years, probably closer to 40. The vise
and the installation are vintage.
I wish I could summon the infallible authority of my 8th grade woodshop instructor, but he has gone the way of St Joseph. My woodworking books are temporarily packed away, but I’ll take a look tomorrow.
Addendum: I watched a blogger and a you-tuber install their vises. Each made different use of the holes. One re-countersunk them from the back and screwed his pad from the back (see my reason why not, above). The other guy decided he liked the removeable magnetic pads, but couldn’t leave those tempting countersunk holes unused, so he screwed through them to “belt & braces” the vise to the bench, which you proposed back when this first came up.
Here’s why you should not do that: Wood moves. It expands and contracts quite a lot differently than metal. The lag screws or bolts or whatever you secure the vise with from the underside define its position relative to the underside of the benchtop, but the top and side of the benchtop will move relative to the vise. If you also lag it to the side, the two sets of fasteners will work together to pull apart the benchtop as it shrinks and swells with humidity fluctuations. Eventually, something in the system must fail: the wood may crack (probable), the vise may crack (less probable), or the bolts may loosen/sheer.