Checked it on my home PC, with i5. Yes, it's definitely better this way. So strike out speed complains.
Others are still here though. Control is somewhat sluggish (especially on the edges), and while I didn't notice any block duplicating, on higher levels movement still not right: it's now not switched along with block on line adding if movement in process, so in result I often switched totally wrong pair, one line below needed.
And I didn't expect that game will end after L9. Is _this_ "Plot"? Huh.