Freezing is not the only reason to add antifreeze . It also helps with rust and scale inside the block. I feel that its better to keep wet parts wet . Letting things cycle wet then dry then wet again puts added stress IMO. Once you have drained the water it only takes 5 min to pour 15 dollars of antifreeze in the raw water hose that goes to the T stat housing. It only takes 1 time to cause thousands in damage why take a chance?