Sorry, but you are all wrong...

Yamaha's SA technology is a quantum leap forward in sample control in a musical setting. No other keyboard of any kind has had this technology prior to the T2. Certain advanced computer based samplers had it, but Yamaha were the first to implement this in a realtime fashion in a ROM based keyboard.

The primary difference, Dave (and yes, given your experience, we are astonished you don't already know this) is that, for legato and staccato samples, the Yamaha's do NOT move the start point of the sample past the transient. They use an entirely different sample. This is revolutionary. Add to that intervalic rules (a jump of less than a certain interval triggers one sample set, a larger jump triggers another, totally different set) and different sample sets for mono and poly playing, and you have a paradigm shift forward in detail.

Now add this to Yamaha's ability in the Tyros series (the MotifXS's SA implementation is FAR more 'pocket protector' than player driven) to correctly switch in the appropriate sample sets based SOLELY on how you play and phrase (mind you, SA2's little buttons are a bit more 'pocket protector' that the old SA system), rather than any non-keyboard technique (pedals, switches, etc.) and you truly have something that is light years ahead of the competition.

Korg have STARTED to catch up here, but while they have the OS down pretty well, it needs to be married to an entirely new set of samples for it to be as effective as SA. So far, as DNC is just a free update, the existing sample set is being retasked somewhat half-assedly, and little in the way of totally new samples have yet to be recorded. But as soon as they do, Korg will have this nailed, as well.

SA is light years beyond sample velocity switching (which has been around for years), and I am surprised that you didn't investigate WHY it sounded so good when it initially came out. It is a PLAYER'S system first and foremost, which is why is is SO good. No arcane button pushes to learn. Just PLAY, and let the technology do it for you. What better system could you ask for?