Dunno whether its different on the NG, but I have been doing the de-select thing on the 737 Classic for the last 10 years.
Its only drawback is when it enters low speed protection mode in the last 200 ft. My experience is that it goes low speed prot mode, plays with the thrust levers. At 27' RA it then goes into retard mode (aka an autoland). Left alone it can lead to the odd firm arrival (understatement). Solution, when ever it goes into low speed prot mode below 200' I click the A/T out...
..Having it there for the G/A is invaluble.