The stats are relative to your rank. And hey, even when I have first percentile stats, people just use the argument that it is easier to pad stats at mid ranks. Sure, but if I am literally in the top percentage, perhaps a slight rank up makes some degree of sense?
Either way, stats are CLEARLY irrelevant if I have the same problem as you, but far worse. If you want the honest truth, the trick to climbing is to do the bare minimum and still win. Lower your mmr, raise your winrate.
Don’t hook off cooldown, hook only relevant targets that will win you the fight. Blah blah blah.