I took a short cut with my DCS and jumped some wires to power feed some of my Atlas turnouts. It took me a while to figure out why Legacy engines (run on DCS) would spontaneously uncouple at times. I finally asked myself (a while after I had done it and had forgotten) if I had followed the star wiring to these turnouts. Well, as stated I didn't. I rewired the turnouts in a star pattern and guess what? No more spontaneous uncoupling. It was my error, but I thought that there were design defects in the Legacy uncoupling system. I actually posted a whole big post about it a while ago.
Also, despite sound advise from knowledgeable people I have no blocks on my layout (other than for sidings). My runs can be up to 76 feet. I have not encountered problems with this. I do star wire feeder wires about every 6-8 feet.
Alan