Just curious what you do and if you think it has an effect on the results.
My preference is to gather a bundle of rare souls and open all at once rather than one at time. I've been lucky with pulls (just pulled 5* alliance general tonight from a bundle of 5 rare souls), but I have no idea if bundle opening helps since my Pharaoh Eddie came from a single sentinel rare soul & my COTD warrior came from a single legendary soul.
So I have no idea if it improves results, but for me opening in bundles is the way to go because it's over with and I don't have to torture myself in slow desperation...
You?!?