I have made a lot of small quilts, a few larger ones, and tied them all. It depends on what the quilt is made for, and the material I have pieced the quilt of what I use for tieing. Most of the crib quilts have one side made of cotton flannel and I use a good yarn, but not wool, for tieing. I pull the yarn through my needle to make a double strand, take one stitch, and tie and cut, leaving ends about 3/4 inch long. Occasionally, I have used "baby yarn" and do a double, x shapped stitch, then tie and cut. The yarn ends make a soft little fuzzy ball when the quilt is washed.
If using a smooth finish material, I then use embrodery cotton, or other heavy thread - tie the same way, but always with the double stitch in the manner that show the x on the back side of the quilt, and usually cut the ends only about 1/4 to 1/2 inch long.
I try to make the ties match the pattern of my pieces in the blocks - either in corners, etc. to compliment the top. My mother used to tie her quilts, and usually had them about the same distance apart in every dirrection. Can't see but what either way works as well, as far as the use of the quilt. And I have found that the ties usually hold better than hand quilting, if the quilt is going to be used and washed fairly offten (crib quilts, especially) Vegas Gram