Yes, that would allow the same amount of memory to work at the slightly faster dual channel mode.
This is the choice we always seem to face when building a new rig and keeping withing a budget.
...Buy 1 stick of 8GB, use the slightly slower single channel mode, but have an easy path to 16 GB later (plus jump to dual channel mode at the same time).
...Or, buy 2 x 4GB now to use the slightly faster dual channel mode, but have to add 2 more sticks later to go to 16 GB
Since today's games are still 32 bit coded, they can only address 4GB of memory. But other resources in our machines will be demanding memory too, so it is best to have at least 8GB for gaming. 16 GB is overkill now, but I imagine it won't be long before games are 16 bit coded.