It does not matter if the attack was a projectile or a physical punch. Characters in DBZ has PHYSICALLY slapped away planet busters and damaged beings that are more durable than planets. I don't need physics 101 to tell me that.
My argument here is that Goku still needs his strength, energy and power to exert that FORCE through his fists. Saying an attack is an attack was the most laughable thing I've ever heard, because on that logic an ant biting a person's toe is just the same as thousand ants swarming a person and killing him or her. And PLanet Buster or not, they would have gotten their asses kicked by Surfer, who is a cosmic entity, who literally could turn them into a napkin to wipe his mouth off. Not a petty warlord or a reject robot designer's pet project.
Who cares if Surfer can turn a planet or a napkin into gold that is irrelvent because he does NOT do it in battle. Surfer's board going right through Goku is laughable. And please care to show me when has Surfer ever destroyed a planet by himself? I am not talking about the fight he had with Morg either because that was BOTH of their powers combined that did that. Surfer can fly into Suns Whoopdey do, yet it does not take much to knock him out, ask Thing and Thanos. I know Cooler is more durable than the sun when he was able to survive Goku's Kamehameha blast and the sun exploded.
"Because he does not do it in battle." This is your great arguement. That the Surfer's abilities are neglible because he doesn't show all his abilities in battle whenever he can? How about this then... Why didn't Goku power up all the way as soon as possible in his battle vs. Cell? Better yet, Majin Vegeta. Why does Goku not just go back to his base form and summon the spirit bomb against Cell, letting Gohan and the other's defend him while he builds it? These are all abilities Goku could have used in these two battles that he never did, that would have been tremendously effective (if a Spirit Bomb from just Earth can kill Buu, I'm sure they could have done it for Cell).
Also, if the Surfer's Board is travelling at lightspeed, and not being a living thing, so thus unsenible by Goku, how is he exactly supposed to dodge the indestructible metal blade that rushes at him and cuts him in half. I don't care that Surfer has never been shown to do that, he can and has on more impressive beings then Goku.
I'd like you to point out a planet Goku has destroyed. While you're at it, do it for the rest of the character's that make up the Z-team, but subtract Vegeta because he's the only one who ever has. By your logic, if a character hasn't done somthing, they can't do it. Goku has never blown up a planet so he is clearly incapable of such a feat.

Yeah right. You've just gone into denial. We've shown you official published material that shows what the Surfer can do, but you refuse to beleive it because you have failed to see it.
I think the Surfer flying into the sun is a hell of alot more impressive then anything your character's have ever done. A) It shows that the Surfer is far more durable then you give him credit for, and B) The character's you name, or at least one, is creditted as a Universe Killer. He killed half the life in the known universe in half an instant. He is Thanos, and the Surfer has gone toe-to-toe with him and survived. So eat your heart out. Not even a DBZ villain, not even Buu, can creditted as able to kill half the universe in an instant. Hell Buu get's his jollies from blowing up planets, now we're talking bigger.
Cooler is a non-canon character. It'd be like me taking a "What If...?" comic and posting it's results as undeniable proof, like the 'Punisher Kills the Marvel universe.' Like that would ever happen. And if the sun was blown up, how did the planet's survive?