What you are describing is called debulking and Rupert is right, it's typically used for preserving the facial nerve when the AN is large.
That said, 2.7 cms isn't really large; large is more like 4 to 4+ cms.
Whether or not debulking would save your hearing is hard to say; it's a crap shoot.
Translab would automatically take your hearing, retrosigmoid would give you a chance of saving it, but the odds aren't good.
My AN was 3 cms, I chose retrosigmoid and ended up SSD; but I knew going into surgery that I had a very good chance of that happening. I decided to take the gamble because I wanted my docs to at least try to save my hearing. I wasn't comfortable just "letting go" of my hearing, because although it was diminished I had good word recognition. I figured if they could save it, great. If not, at least we could say we tried our best.
I don't regret my decision, but you need to do what you think is best for you.
Jan