No, not grappling. What I mean by "tackle" is something more like a fishing line.
OK, that's a cheesy analogy, but what I picture is something more like individual lines that are fired out by the marines. All the boarding ship would have to accomplish is a close enough match that the marines could stand the sudden acceleration as the lines pull taut and they are suddenly sailing along behind the enemy. Just reel in, apply a limpet mine to the airlock, and proceed from there. It'd be much more difficult to intercept 12 individual targets (or however many marines make up a boarding party) than it would be to down a single assualt craft, which helps explain why there's no chance modelled for interdicting the boarding party before it reaches its target.
My own image of the marines includes something more like a full exoskeleton system. Certainly full life support would be a must. I suppose you could crack the airlock security and close it behind you but that'd be time consuming at best. I think any way you are going to get into the ship will lead to decompression. The marines would need to be able to first fight in that environment, and then survive in it long enough to patch the hull integrity back together and restore the atmosphere.
I'd assumed the boarding module was disabled after the boarding attempt because, well, the marines are either dead or fully occupied maintaining control on the newly captured ship.
Aaaaanyway, I'm just rambling about my own half-formed mental image. I don't see any flaws in an assualt pod concept, as long as they don't use those cheesy fighter/lawnmower engines for power. They'd get left in the dust trying to close while riding on one of those.
