i always start at the 1/4" point- that way if i have to do any trimming at any point i'm not going to clip my hand stitches.
i love hand piecing- the precision is great- things just seem to go together so much better than when machine piecing. but i do my prep work- meaning i draw diagonal lines- put dots at 1/4" spots- what ever is needed the little bit of extra time spent on prep saves me tons of time as i go along- and the precision is great.