It seems you recall correctly. The old definition seemed to additionally include “efficient”.
Muehlhauser & Salamon (2012):
For our purposes, “intelligence” measures an agent’s capacity for efficient cross-domain optimization of the world according to the agent’s preferences.
Yudkowsky (2013) (also expands on this definition):
I usually use a notion of “intelligence ≡ efficient cross-domain optimization,”
See also Efficient Cross-Domain Optimization — Eliezer Yudkowsky
It seems you recall correctly. The old definition seemed to additionally include “efficient”.
Muehlhauser & Salamon (2012):
Yudkowsky (2013) (also expands on this definition):
See also Efficient Cross-Domain Optimization — Eliezer Yudkowsky