What you are calling a "foot reef" sounds like it is actually a flattening reef. Flattening reefs are intended do just what there name implies, flatten the sail when the wind pipes up. Properly rigged they pull down and aft which pulls a lot of cloth out of the sail on a bias which when used with increased main halyard tension, a dropped traveller and increased sheet tension (and increased mastbend if that is available) greatly flattens and depowers the sail.
No matter how blown out your sail, I would expect a flattening reef to take some belly out of your sail which makes me suspect that perhaps the reef is not run correctly. The reef lind generally leaves the sheave at the aft end of the boom and is tied aft of the reef cringle on an eye below and aft of the cringle. If not properly lead it will not provide the necessary tension in the right direction.
That said, it does not mean that your mainsail isn''t blownout.