The greenhouse that he has works great for getting tomato starts outside earlier, and you can grow any common garden vegetable in them all the way through I would think.
When I was growing up we had a slightly larger greenhouse with the transparent & wavy fiberglass sheets covering a 2x4 wooden frame that was about 8'w x 12'L, with 8' walls and a 10' tall at the peak.
The light coming into the new cloth greenhouse seemed about as bright as that.
It cuts maybe 25% to 33% percent of the light intensity, but it's a very bright & diffuse light when inside it.
You might want to check out some really cool DIY vids on youtube where people show step-by-step how to build a good portable or temporary, or even permanent greenhouse for very little money.
$200 or less.
And it would let you have a clear roof and even some clear panes extending down the walls from the roofline to let more light in without sacrificing privacy.