The operator I fly for uses a CI which "approximates LRC" - and is not an application of CI as such - at either end of the range COI "0" is used for min fuel and CI 300 for min time, with a "normal" CI 60/70 being used as the standard. If you think of CI as "LRC with brains" ie, varies with wind as well as weight, then we use it as a "smart" LRC speed generator - but I guess lots of performance engineering departments have their own ideas - I would be interesyted if any operators actually use CI as originally intended, ie, a consideration of total actual operating costs v fuel v time ?