When I first tried to assembly the deck, I found I could not accomplish it. I could not make the final connections without bending struts! I made the mistake of having the diagonals go:top--to-bottom, bottom-to-top, top--to-bottom, bottom-to-top, top--to-bottom,Then I realized that if they all go top-to-bottom, it creates a degree of freedom that wouldn't otherwise exist. If the diagonals are too long or too short, the deck pentagon can rotate to accommodate the error. It means that the rectangle formed by two adjacent risers plus a dome top pentagon strut and a deck pentagon strut will become a parallogram. But, even if it does, it will still be rigid once the whole structure is assembled.