Terrible. Toss it in the trash. Oh,and let me know when and where you do just so I can verify that everything went well.
Since it's an acoustic, you're probably not doing any big bends on it and won't feel any roughness from the porosity of the wood. I wonder, though, if you applied boiled linseed oil on the fretboard would it fill in those little openings in the wood? I've never done this, so maybe someone who has can comment.
i dont like that look either.Personally my solution is to finish porous rosewood boards either just to fill in the pores and make it a little bit darker and super smooth or going into a full blown glossy finish like i would do with a maple board. I sand the fretboard very lightly(not side to side and change the radius, but from fret to fret) with 400 grit sandpaper so there are no oils and the board is clean to bind with the finish....then i start applying finish and i either spray lacquer on top or my favorite:Applying a drop of water thin superglue on each fret and spread it throughout the fret with a folded paper towel....you do that several times and you level each fret with higher grit sandpaper(500 or 600) until your board is all smooth and without pores.... if you want glossy results keep pilling up the coats and level later resulting in a glossy darker rosewood fretboard that doesnt look annoyingly ugly anymore....here is one example.
Oh dear. It's like one of those horrifying passages in Swift about the brobdingnagians. Yeah, that's what it is. I'd get that thing to the nearest leper colony pronto. And please don't post that kind of filth ever again.
Here’s something different to worry about that actually matters. Your leather sound-hole decoration is likely acting as a damper and not allowing that lovely top to vibrate to it's fullest potential.
I have used dark shoe polish wax in the past, rub onto the wood so it fills the grain, let dry, polish. Repeat until the board is nice and smooth. It seems to last for a long time, and it's easy to reapply.
I like the idea if it darkens the fretboard but I'd be concerned that the polish would come off on your fingers with the slightest perspiration.