As far as deliberate sabotage, I think that it goes on occasionally for lower models.

I think that Yamaha deliberately keeps the TALK ON/OFF and VOCAL HARMONY ON/OFF buttons off the PSR-S910 because there is not very much feature difference between it and the Tyros 3 while there is such a big price difference.

I thought of sabotage with the PSR-700 - the top midrange keyboard of the time about 12 years ago - which didn't have a floppy drive even though this was widely available. You only had 1mb of memory.

I really thought of sabotage when the PSR-2000 and PSR-2100 came out. The predecessor, the PSR-700 had two intros and endings, as opposed to three for the top dog, the PSR-9000. They gave the PSR-2000 and one year later the PSR-2100 three intros and endings with only one button each to activate them. You had to go into a submenu to choose your intro or ending! This was so inconvenient, that I missed the mere two intros and endings on my previous model.

They also had to shuffle through floppies on these models even though there were many other cheap mass storage options that had been available on computers for years.

Starting with the PSR-3000, I feel like Yamaha started to get things right.

I do get frustrated though. I have a patter between songs that makes me need to use the TALK ON/OFF function, and I get frustrated that there isn't a dedicated button. At least once a performance, I start a song with the TALK on which takes away all the reverb from the song and voice.

Beakybird