I knit socks toe up 90-95% of the time. My reasons are good for me and may not work for you. I knit with magic loop so any discussion to follow assumes the sock is in 2 halves (front and back).
I knit toe up because:
1. I do a good job at starting and having a nice smooth toe. My typical start is Judy's Magic Cast on My difference is I leave the cast on pretty loose. After I've knit several rows I'll go back and tighten up the loops. Works great every time.
2. I like my toe increases better than my decreases. When I increase I start the needle with knit 1 then on stitch 2 knit into front back of that stitch. At the end of the needle I do the knit front and back on the 3rd stitch from the end then knit the last 2. That puts the make 1 bump between st 2 & 3 on each end. This also give a bit of body on the 2 edges of the sock. Notice the make 1 stitches just blend in nice and pretty.
OK - back to the short row on the heel.