I concur with many of the points mentioned:
1. Yes, the boat
can be sailed with the weighted swing keel
partially or all the way up.
2. As the boat
still has some swing keel
exposed under the hull
when fully retracted, it can be sailed close-hauled, albeit at a somewhat lower point of sail, with increased leeway, and greater heel. Other boat models where the keel fully retracts into the hull
(beachable) will not sail to windward well.
3. Sailing downwind, with the keel fully retracted, the wetted surface is reduced and the boat will go faster. (If the boat is heavily laden, it will tend to get a little squirrely as hull speed
is approached. Be careful to extend the keel in high wind
before turning off a downwind run, as it will tend to broach (round up) as the turn is made.
4. I will add that the CLR can be adjusted aft by retracting the keel slightly, to reduce weather helm
(if needed, typically in higher winds).