imbabci2

I have 30 year old oil stained cedar lap siding on my home. It has blackish spots, looking a bit like mildew, on many areas. Many of the nails are popping out. Many knot holes are missing. it appears very dried out. There is also some edge curling on the sunny sides of the house. I've been told by a friend that cedar can be saved: bleach it, caulk the bad areas, then apply a couple coats of stain. Would anybody care to comment?