Only on my second reading of this paper I started understanding what the paper was about. The authors have done so much work that it is very hard to explain everything in mere eight pages. I think quite a few details could be moved to supplementary materials and more emphasis placed on key findings. For instance, describing results in figures rather than text and using the gargantuan abbreviations only when absolutely needed would already be a great improvement (e.g., Line 145; Lines 165-170; Lines 220-232; Lines 280-292). Specifically, I think I would find the following structure more clear: Just have a single figure with a FF CNN, (C-)BPTT / (C-RBP) hGRU / convLSTM, so that we can clearly see how each additional thing helps.