Gear changes at low rpms

Maybe it's everybody's SVX, but I'm kinda curious as to why the car always seems to have to search for a gear upon acceleration after the RPMs drop below about 1K. Even if going 10 MPH or so, in gear 2 with the Manual button pressed if you let off of the gas and then accelerate the RPMs first drop down before going up. What is that? Is it a TPS issue?