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Yes. The smaller the volume behind the throttle plate, the smaller the pumping losses (as I understand it). ITBs are an improvement, but you still want some kind of plenum with a single opening, and you'll want to use mass airflow to meter air, because a MAP-based system typically doesn't work well with ITBs.
Even better than ITBs is moving the "throttle" right to the valves. Honda's R series engines (2006+ Civic) vary the intake cam to control valve opening and therefore throttling, under some conditions. It still has a throttle plate, but that gets held wide open when it changes to variable valve timing throttling. Honda claimed a 16% reduction in pumping losses over their standard VTEC system.
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