I do 10-gallon batches that I chill with an immersion chiller that I remove after chilling the wort while stirring, and then wait at least 10 minutes before runoff first through a fine mesh strainer. The first bucket filled gets considerably less trub in it. I leave as much trub and pellet hop spooge behind as possible, including typically at least 1/2 gallon of liquid. Although both buckets are filled the same and sit in the same fridge ferment chamber, sometimes one does not come out as well as the other all other things being equal while practicing quality sanitary practices. I figure the primary reason for a difference in flavor and occasionally color too, is when I transfer too much trub/spooge into the second bucket fermenter. I generally need to transfer some trub since I max out my keg kettle to yield 11 gallons/5.5 gallons wort per bucket, each of which yields 5 gallons of finished beer into a corny keg. For batches with really heavy hop load and break material, to reduce the amount of trub transfer instead of running off via the kettle's ball valve I'll transfer from the top down using a siphon.