MoonShadows said:
I guess one can find just about any opinion since everyone has one. 
My experience tells me that diffused works just as well both in providing adequate light and warming the soil. It is the temperature of the greenhouse that warms the soil, not the sunlight. Also, with clear, you run the risk of burning tender plants; the opposite is true with diffused light. I would be interested in what you decide and your results.
I'm absolutely going all diffused. It's what my gut said but multiple sites stated the quote I posted in some form or another.
