Tell us about yourself!
That being said, you should re-do your measurements to capture a power reading instead of a voltage reading, as voltage alone is a genuinely useless piece of data when trying to calculate the power out of a solar panel. Talking through this concept with smart & experienced solar people, I don't think your arrangement is going to be as good as a flat panel in any condition. You lose too much power from that first bounce (by being at a hugely inefficient angle) for subsequent "bounces" trapped in the valley to make up for that loss. Would love to be proven wrong though!
With this arrangement, given the certainty with which 50% of the cells will be at suboptimal shading at any given time, anyone building this should put the two parallel subgroups of cells into two separate electrical circuits with individual MPPTs, and probably voltage conversion. This will let the two groups run at peak efficiency instead of bringing down the max power to the level of the indirectly-lit subgroup.