If I recall - Boeing training used to make a point of "CRISP" landing procedures as opposed to "HARD" landing & "GREASED" landings. There have been several incidents due to pilots greasing the airplanes on Sooo smooth that the air-ground logic gets confused & the airplane never gets into a "GROUND" mode where you got spoiler & thrust reversers. Recall that the air-ground sensors for these systems are inductive or magnetic prox-sensors - who in my opinion need a sharp transition - recall the levels of protection on these systems - IE spoiler & reversers on final are somehing A/C mfg's go to great lengths to avoid in the air - particularly on final for obvious reasons - therefore when in doubt - lock it out. With the advent of high thrust twins such as the 767-300ERs - pilots were performing aircraft carrier landings - slow with lots of angle of attack to grease these birds on the runways - of course this also exacerbated the occurrance of tail strike as well - morale - you should always follow the manufacturers procedure - which I think is a "CRISP" transition from air to ground - I leave that up to you research more .. IE something between popping stowage bins and ....
Regards,