Cool guide

This method is called Dual. The technique behind this is, you are able to clear just as fast as a whole group and are able to get drops only to two people, giving you a 1/2 chance instead of a 1/5 chance.

I'm pretty sure the forum consensus, confirmed by devs, is that drop rates are independent per player against the loot table. Your 2% chance at a good pink doesn't change with more or less players also getting drops from the same boss. It only seems like it does because your confirmation bias has you remember when other ppl get pinks ( which really does happen 4x more frequently in a full group) more than when no one gets any ( which really does happen more often with Dual).