I do it, although not well. Just finished an Irish Chain quilt, where I FMQed a Celtic knot in the centers...wow, what a challenge, since I had to retrace some of the places (in order to achieve the over and under look). To make it worse, the fabric was dark and busy, so I could barely see my chalk lines. I used straight lines (using a walking foot) for a big part of the quilt, and then an easier Celtic design in the border. Marked the border using chalk also...and it was blowing off as I went along. Whew! Glad when it was done.
I felt so-so about the effort until I washed it ... and discovered that most of the poor workmanship is lost in the crinkles :-)
Still, I keep trying. Still tricky getting the tension right. For some reason my machine (Janome 6600, with the blue bobbin case) seems to prefer polyester thread. I suspect if I get the machine serviced (timing issues) it might be more forgiving of other threads.
SOOOOOO hard keeping the stitches even!