Hi Doc,
the guy where I used to buy my technics keyboards used to play in full piano mode.
He used to sell Yamaha & Technics, and, according to him, Technics did a far better job of following chord changes ( in piano mode) than Yamaha. He showed me on a number of occasions, the differences. Eventually it even sunk thru my thick skull. haahaa
He was even able to include piano runs ( in piano arranger mode) without affecting the chords.

I sometimes play full piano mode on my Korg, but I'm not expert enough to comment on whether or not the chord recognition on my pa800 would be better than on the pa80.

A check of the manuals might say whether or not something has changed as far as chord recognition settings go.

best wishes
Rikki