...let's see...IIRC...the early direct drive machines did do a spin drain but I'm not sure when that stopped. A lot of the newer models erroneously spin drain once they get some wear and tear on them....my TOL Whirlpool did. You can still trick them into spinning by opening the lid during drain, but I can't imagine that being good for anything in the works. :)

I haven't noticed the mechanism being any more or less agressive on the new vs. the old machines. The older standard capacity machines tended to be more aggressive than the large tub machines. My friend had one with a straight vane that was a genuine Shredmore if overloaded. Same thing with my ex's BOL Whirlpool DD.

I know that Kenmore initially had the exclusive Dual Action agitator vs. others, but that was way back from the belt drive days. Newer Kenmores are virtually identical to my Admiralpool. As far as favorite agitators go, my own personal favorite was the Super Roto Swirl from our 1981 standard capacity Kenmore. It was gentle but got the clothes clean every time.

I am uncertain as to what year Whirlpool went to a neutral drain in the DD machines but it was relatively early (by the mid-80s).  In my experience, if your DD is spinning during the initial drain it means that the neutral drain assembly inside the transmission is worn and needs to be replaced.  It is an inexpensive part that involves dropping the transmission and taking it apart to replace.  Given the labor involved, I have always just replaced the transmission with a rebuilt one.  It only takes about 20 minutes to change out DD transmissions.  I also usually replace the spin clutch while I have it apart. 

It is a problem when a DD starts spinning during the drain for two reasons: 1. It is very hard on the spin clutch which was never designed to spin with a tub full of water, and 2. If you have a full tub of water it often throws water out over the top of the tub at the beginning of the spin which gets all sorts of stuff wet that shouldn't.

When Direct drive first came out it was phased in on the smaller and lower priced models.  So that may account for why some of the earlier machines were rough on clothes - the tub was deep and narrow and less spaced meant the clothes rubbed together more.  The larger machines had direct drive phased in later, and the Limited Edition was the last of the belt driven Kenmores around 1986.  I remember them in black - It looked like a washer and dryer Darth Vader might own.

The Gentle Wash system also helped with aggressiveness.  Regular cycle starts at high-speed agitation, switches to low speed at 6-mins remaining.

Three-speed motors also help, with the extra-low speed.  KitchenAid three-speed machines used the MEDIUM motor speed for HIGH-speed agitation, the LOW motor speed for low agitation.  HIGH motor speed was used for spin and drain, not for agitation.

A neutral-drain tranny malfunctioning into spin-drain has nothing to do with the motor coupler.  It's caused by wearing of parts inside the transmission ... and can also be caused by thickened tranny oil if the machine is run in a very cold environment.

My grandmother's LA7400XMW2 bought in Nov 1984 (S/N C43505625 - 35th week of 1984) still did spin-drain.

I like the agitator with the lint filter...with the pet hair I deal with, wish mine had it.