It now results in funny go-arounds, as the Throttle has to be manually set by one of the pilots.
"TOGA, flap 15" gives you a nice FD, but that is all.
Sounds exactly like a manual G/A.
I've not used this 'deselect' option, so please may I confirm something: if you deselect A/T on approach are manual thrust changes still available? If they are then I see its use as making no difference to the piloting technique, even in the gusty flare. From reading the comments it seems like a safety net. It is too many moons since my departure from B757/767 to B737 family. I seem to remember B757/767 having such a mode. When I went to B737, along with many other former B757 pilots, there were those who investigated the B737 auto-throttle and decided it was possible to configure it like a B757. The CP & HOT, who neither had B757 experience, poo-pooed it with Boeing's blessing, so they said.
"Not normally recommended," does not mean "thou shalt not...". If it was a 'thou shalt not' by the manufacturer then perhaps it should not be possible at all.