Ok guys I have tested it and now am 100% sure I know what it does.
the whole finding less randoms thing is a pretty lame guess tho guys
What it does it lower the amount of trophies you lose at reset I forgot to grad a stack from gs when I gated the other day and noticed I only lost like 7 trophs out of 90 so I thought I would just leave it there to see if that what rec did and sure enough 4 - 5 days later I still have 42 of them.
my rec is like 92 I think, but there you go nod thats what it does.
Take a toon with high rec and a toon with low rec and do the test every day for the next five years, then let us now the results. For a statistical test like that you need hundreds of samples minimum, preferably thousands.