Massive oil leaks.

While I believe your problems could very well have been caused by improper crankcase ventilation, I don't agree that you MUST run a PCV valve. Positive Crankcase Ventilation valves came about on vehicles to reduce emissions. I've personally vented plenty of engines through both valve covers via breather caps, and so has just about everyone I've known... With zero issues. You've definitely got an issue, but I don't for a second believe it's because there is no PCV system in place.