Super Saiyan Grade 3 is stronger than Super Saiyan 2

in DBS when Trunks sparred with Vegeta, he first went ssj2 and then went grade 3 to troll Vegeta into thinking "Trunks is dumb he is sacrificing speed for more power".
In Dragon Ball Z Cell admited that Trunks was stronger than him, no, he didnt say "lmao im using 20% of my power and you are stronger than that if i go 21% i whopp ur butt lmaooo". No, he straight up admitted Trunks was stronger
In the manga Trunks grade 3 didnt land a single punch on Cell, had he done it he wouldve messed him up bad, the grade 3 attacks landing are just anime filler.
When cell survives his self destruction what is the first thing he does? he kills Trunks with a sneak attack, he knew that if he beam clashed with ssj2 Gohan and Trunks attacked him with a transformation stronger than ssj2 while he was defenseless he would die.