Um... we're sure it's an LC card? As in the 020 that got half it's bus width stolen???
What would it have been used for?
Just because a machine is slow doesn't mean there's nothing you can do with expansion on it.
There's
loads of potential use cases for running an LC-series machine with multiple slots, like this. I often talk about how
in effect there aren't options for these slots, but if you can find the card there really was a variety of different
Network + IIe, Network + Accelerator, Network + Accelerator + IIe, the three of those plus a graphics card. Heck, there's plenty of use cases I can think of for just, one LC with two ethernet cards.
In addition to that: not all LCs are the LC/LCII -- the LCIII/III+ and 475/605 (plus the 630/580 and the 5x0 series, although these risers won't fit in those) all have significantly improved architectures which make these upgrades make
even more sense.