I only have a few production knives with micarta scales and they soak up water like a sponge. One is a Becker BK4, I have a El cheapo condor and a ESEE Izula2. I think that is what makes them so good for a woods blade, they are very grippy when wet. I would think blood would make the scales stink and deteriorate. I'd say y'all are right with the customs, they probably are sealed. I don't own one so I wouldn't know. Po boy...
Micarta is pretty much impervious to water, blood, about all the common cleaning chemicals to include oil or gas and a wide range of cold and high temperatures. It's about as indestructible a handle material as can be had. Add G-10 in there as well. The idea the scales would soak up blood and stink/deteriorate isn't accurate from anything I've read or my experience with several dozen micarta scaled knives.
