I understand that Acceleration is for people who do not have much time to play, and that the grinder upgrade is for people who want to play alot. As of now, I have no real need for the grinder upgrade, but if, perhaps it was to stack with acceleration then I would consider buying it.
It may be a bad idea, but I was thinking that with grinder + acceleration, the experience gained by a user would be double the amount gained with only grinder. It seems logical to me, and would probably encourage me to actually dip into my rested time and playing when out of RT rather than just playing my rollover rested time each day
What do you think?