I think it's a power steering PRESSURE sensor. (But actually, I don't have the right generation Accord...) It probably looks kinda like a little sensor with a wiring harness plug. Not many things have wiring, that's attached to any of the power steering plumbing.

Haynes book sometimes is 'creative' with terminology. Maybe they're talking about the VSS on the transmission.

edit...
It probably just sticks out & gets in the way. If you don't remove it, you probably break it off when you lower the transmission. Dropping the transmission usually takes a little bit of brute force anyway. Just look around real good for ANYTHING that might get in your way; and any plugs, wires, hoses or stuff that's still attached to the transmission. Just in case Haynes forgot something.