You do freeslice or cycles for the edges? that alg should work. Doing centers and then edges is a valid method, but you really want to use Yau4 for 4x4, it's a lot betterJust picked up 4x4. I do all 6 centers first and then do edge pairing but I noticed that, somehow, the centers swap positions after I'm finished pairing the edges. Maybe it's because I use Dw R' F R F' R U' R' for the last two edges? Not sure. Also is it viable to do centers first then edges?