As it was explained to me the EXP button gave climb at Green Dot and Descent at MMo or Vne, this led to several alpha prot or high speed excursions. It was banned from use in our airline before I joined in 2000. Since then, all of our old narrow bodies have been retired and all the new ones have the ALT button instead. All wide bodies, I understand, have ALT button, which has the same function as pushing the VS button. I have also read somewhere that EZY had an incident years ago where someone pushed EXP insted of APPR, which must have caused a bit of excitement.
As regards the thread topic, there but for the grace of God.............
With regards to sim training, IMHO, it has been become more TRAINING and less TESTING, these days I come away from nearly every sim having learnt something new, in the old days I came away from a sim with a huge sigh of relief. Lets not revisit the past, but with the amount we are expected to cover in each detail, maybe more time in the sim for all of us would be beneficial.