Well, it's not really Lucas-ian in its "newness". Scott intended to at least hint Deckard was a replicant all along. Basically, Scott didn't have final cut on the movie. Without any reference to verify details where I am, Scott ran over-budget/missed a deadline and the financiers (Ladd?) took control of the film. After negative test screenings, they then removed all of the hints toward Deckard as a replicant, added the noir-voiceover, and added the driving "happy ending" footage at the end (ironically from (filmed for?) the beginning of The Shining.
I don 't think that Scott ever made any pronouncement about that question until after they released the work-prints as "director's cuts" and then went back for a real directors cut in '93 or '97? I can't remember which. At that point he came out and said Deckard was, for his intention, a replicant.
That said, I hate the idea of Deckard as a replicant with the passion of a thousand suns. Future Noir has a section where Hampton Fancher traces what he thinks is the genesis of this idea to a version of the script where at the end as he watched Batty die, Deckard remarks that he and Batty "were brothers".
@Tom, the only other times I can remember him interacting with other cops are when he is identifying himself to the prowler patrol by the Bradbury, after shooting Zora, and the cut scene in the hospital visiting Holden.