It's the complete reimagination of the character -- and Nimoy's direction to Curtis to not look at Alley's performance -- that leads me to conclude that Nimoy felt Alley's Saavik was somehow misconceived, so when the opportunity presented itself for the production to walk away with Alley's salary demand, he took it because it served his vision. The lack of a counteroffer and an attempt at negotiation, which her agent was surprised by, is also telling.
