If I've not practiced the downhills for awhile, I'm quite uncoordinated on them the first session back. The second second is much better though. You get used to them quickly, and the more practice the better.
A lot of people try to push too hard with each stride on hills, causing the cadence to drop and the effort to increase. Your strong quads might tempt you to do this, but you can focus on keeping your cadence light and quick up the hills. This might feel like you're not covering much ground with each stride, but that is okay, because you're running lighter and you get up the hill more quickly this way.
The downhills are not just a matter of being coordinated in general, but a matter of gaining that coordination from the practice of running them regularly. Once you gain the coordination, then it's easier to maintain and get back. Just focusing on your form won't do as much as actively practicing the downhills regularly and running your best.