However, I see nothing wrong with this. By defining the number of ledgegrabs, the rules would be defining the point of excessive stalling. That means that the stalling that 30/40/whatver the LGL is number of times is *acceptable,* just as CGing to 300% is. Once it goes beyond that number, however, it is considered excessive stalling and subjects the player to a DQ, just as CGing someone past 300% does.
In addition, the nature of planking is that once you start, it is hard to stop without getting hit. Lets say that by IDCing to get the complete invincibility, you avoid a snake nikita-dropping the edge. He is thereby forcing you to keep planking, or get hit, which brings you closer to the number. So if you force the MK to the edge early in the match, it is possible that by forcing him to either plank or lose the percent lead, you can cause to plank past the point where he is excessively stalling, if he had any plans on stalling the last 2 minutes by planking.
*as too the DDD example, which is one of the only cases I could see happening: If the DDD was good enough to predict the snakes every move to keep him offstage/force him to grab the ledge, without the snake either recovering to the stage or getting from ledge to stage successfully, there is *no* reason that the DDD shouldn't be given the win. Again, if you treat the LGL as a means to prevent excessive stalling, it would be agreed that the snake recovering to the ledge over and over (or the game and watch planking, or the character using tether recoveries 3 times after grabbing the ledge), once going past the LGL, was excessively stalling one way or the other (either by being outplayed and forced to the ledge, planking, or simply tether-planking the ledge too often).
This way the restriction does not affect only the MK matchup, but serves to define exactly how much grabbing of the ledge during a match for any character is too much, and punishing all characters that abuse the ledge to any degree for over abusing it.
...
As to scrooging, again, this is not a MK only ability, and a rule that affects MK is not necessarily only affecting him, but fixing a problem with the game the same way limiting stages or chain-grab durations does. By saying that one may only scrooge x times without grabbing a ledge, you prevent all characters that can scrooge (gliding characters, jigglypuff, sonic, lucas, and anyone else that can circle-camp) from stalling by going under the stage. In addition, along with a LGL, you make people trying to stall with circle-camping have to worry about being DQed for excessive ledge-stalling, as defined by the LGL.
In summary, the problem you guys have with the LGL/scrooging is that you seem to be looking at it in 2 fallacious ways.
1. Assuming that it should only affect MK, rather than limiting the ability to abuse ledgegrabs/circle-camping to stall by any character (just because MK stalls better doesn't mean other chars should be allowed to excessively stall.)