Cool idea, but it was lacking in some of the fundamentals. When the two sides aren’t lined up evenly, it’s hard to know which lines are connected to each other. I cleared a few lines that were visually disjoint, like it rounded 0.90 down instead of up, kind of thing? And placing a tetromino in the middle really never ended up the way I expected.
I think both of these problems would be fixed if you forced the two sides to align to row boundaries.
But all in all, this was fun to play. Thanks!