WFOpt optimizable vs being optimized

Currently whether a collection of WF parameters are optimized during WFOpt is controlled at TWF input part via optimize=yes.
This is option is confusing. I'd like to make a distinction of two concepts. Optimizable and optimized.
"optimizable" refers to a piece of WF implements optimizable parameters. This is a knowledge TWF knows at compile time.
"being optimized" refers to optimizable parameters actually being optimized during WFOpt. This is a state in WFOpt drivers instead of in the TWF.
I'd like push new implementation following this notion.