Smittie, yes, the turtleneck sweater has buttons down the back. When the collar is taken off it can be worn like a cardigan with the buttons in front too.
I didn't think about both dresses being tunics technically. I'm getting the black and denim sleeveless one. I considered the shirt dress one that can be shortened to a shirt, but I have a boxy shirt dress and I have a few button up shirts that serve the same purpose as this one, so I couldn't justify it.
I'm especially hesitant that the sleeveless tunic isn't going to be weird and gapey at the armholes, but I was too intrigued to not try it, especially after I read that the straps are adjustable and the dress can be turned inside out.
I like the novelty of the whole thing. I get too bored to really stick to 5 items, but I am really impressed by the thoughtful design. I think it'd take quite a while for a coworker to notice you'd been wearing the same thing over and over. If the quality and function are good I think it could be a great transitional capsule for someone who has recently changed shape. It'd be a pretty sweet post-partum gift for someone really really special.