It's amazing what players will try to justify. It's just a question of where the GM chooses to put the foot down.

Notice how the players very carefully have not pointed out that you'd need some insanely unrealistic reflexes to stand a chance of deflecting blaster shots with a sword. The "laws of physics as used by players" are very selective that way.

Unfortunately for this particular strip, there is a paucity of suitable frames of the film in this scene for capturing images of Qui-Gon and Obi-Wan doing suitably interesting things. Unlike DM of the Rings, where Shamus Young regularly found great screencaps of the characters displaying all sorts of emotions, the acting here is just too stoic for anything like that.

Transcript

Qui-Gon: I'll use a blaster in one hand, and the laser sword in the other hand.
GM: You can't. The laser sword is a two-handed weapon.
Qui-Gon: Okay, a blaster in each hand, then.
Obi-Wan: No, no, the laser swords are clearly superior. The robots couldn't possibly miss that many times if their weapons were any good.
Qui-Gon: That was just random!
Obi-Wan: The blasters are clumsy. The swords are much more elegant weapons. And they serve as shields too. A blaster can't do that.
Qui-Gon: If I aimed directly at an incoming shot...
GM: No no no! Absolutely not!
Qui-Gon: All right then. Sword it is.
GM: Good. Now, the Trade Federation have sealed the—
Qui-Gon: I carry all the blasters so we can sell them later.