That's a bit of a reach. The episode dialogue doesn't specify the weapon being used, and it looks more or less like a standard photon torpedo. The term "magnetic pulse" is part of the walla, something Spock (IIRC) utters in the background, not necessarily referring to the weapons themselves but rather to the effect their impact has on the hero ship.
It's already bad enough that TOS-R turns the attacker into a battle cruiser (when plot requires that the heroes destroy it without breaking a sweat, and thus would benefit from the use of a lesser vessel such as Bird of Prey or Raptor or somesuch). Introducing an all-new weapon type is an unnecessary complication as well. They should have done the reverse, using a familiar weapon fired by a novel ship type... Perhaps from under a cloak to boot, since the Klingons got the drop on the heroes somehow.
I'm not sure about the dramatic impact of hull vs. shield. It should suffice that the shield be visually and perhaps aurally interesting. The Gungan shield from everybody's favorite Star Wars movie made really nice sounds when hit... Combine that with cool VFX that somehow directly indicates the weakening, and you get a battle scene. But if enemy hits always create big gaping holes in the hero ship, it becomes a bit tedious: all those hits, all that damage, and still our engineer hero can patch everything together within the confines of the film budget (i.e. no spacewalks or a staff of hundreds toiling like ants)? The "drama" of holes in the hull is diluted pretty quickly.
Timo Saloniemi