>>1116 back, finally got it done!
Cooked them as described. No sqeezing, soaking or anything like that, just shredded straight into the pan. Keep in mind my scale might not be very accurate, take as rough numbers.
Started out with 334g of potatoes.
After peeling, 284g. Another 6g didn't end up in the pan as well, the stumps you end up with after shredding. Another 3g stuck to the shredder.
So 275g goes into the pan.
Ended up with 163g of hash browns, though about 40g of that is oil. If my math isn't off that means 55% of the (prepped) potato weight is turned into steam.
End result is that only 37% of starting potato weight ended up in the finished hash browns.
The hash browns were delicious.