Not sure why you would want to do that, never heard that theory before.
Unless you’re trying to get the kart to bicycle… or if in the 4-stroke world there is a different definition of “hopping”.
Rental 4-stroke hopping perspective: rental kart weight makes this even more of a thing. For some reason, the heavier the kart, the more likely and more savage the hopping seems to be.
At big Lo206 events thats why you see people either installing shorter hubs or cutting down their rear axles, to narrow the rear end to free it up and to combat against hopping and binding.
I watched a guy at CKNA who cut his axle down substancially, but he canablized another axle and cut rear axle extensions at various lengths to add them as inserts when he needs to go wider at different tracks. He had (I think) 3-4 different inserts from 1/4 inch wide all the way up to about an inch. Pretty smart idea, and this guy almost always gets on the potiuem.
I was literally just having this conversation with our local track mechanic, and he was even telling me that he thought it was funny how you have to do the opposite in 2 stroke vs. 4 stroke. Being primarily a 2 stroke guy, he said he has to go against his initial instincts when wrenching on 4 strokes.
As a layman I just wondering why it was opposite, as in my mind, you’d think it’d be the same. Must be because of the lack of power 
Well, narrowing the rear will “free” the kart up in the sense that it allows the inside rear to lift more easily. But I think the difference might be that a 4-stroke kart is always running very narrow to begin with, so when a 4-stroke kart is hopping, it’s from not lifting the inside enough perhaps. It’s definitely a different tuning philosophy to run the super narrow track widths.
Maybe our resident 4-stroke experts can chime in.
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I am not a 4 stroke expert, but I think I can help. For starters, the tuning philosophy is the same. The engine doesnt matter to the kart (necessarily). What matters is the kart, axle, tire compound, where/how hop condition exists, etc.
Now, those things are often very different for a 4 cycle guy vs a 2 cycle guy, but the strategy is the same. TJ is spot on. What is often different is what is causing the hop. Overloading the outside rear is not the only thing that can cause a hop. Setting the inside rear down too soon can cause it or even not lifting the inside rear enough.
In a 4 cycle, we rarely use enough lift to actually overload the outside rear. Mostly because we don’t have the power to overcome using that much energy. However, it does happen. All of this needs to be thought about when “fixing your hop issue”. Hence, why people may all fix “hop” differently. Because they are all actually fixing different things.
As the late Al Nunley would say. “This is called tuning and tuning is hard.”
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I think people forget that that most 2 strokes run a softer tire than 4 strokes too. Every time I had a hop in TaG, it wasn’t until after about three or four laps and the tires starting coming in. Prior to that it was more a flat slide. When the tires were still cold, they didn’t have enough bite to initiate the hop. It wasn’t until they warmed up enough to start gripping up that the hop would come in. In the case of a 4 stroke, the lower grip means to get the outside tire to bite more you have to go more narrow on the axle. Cutting the axle allows for a more narrow track as well as less flex in the axle and less inside rear lift.
Another suggestion to consider…Are you sure the track isn’t the cause of the hop? I offer this because it has happened to me. It wasn’t till I was talking with another karter that had the same problem in the same place that we discovered there was a ripple on a cerian line exiting a corner. Changing the line reduced the hop. As a new karter, if you can watch others in the corner you are struggling with it may give you some ideas to try as well.
The vid he posted looks pretty spot on line wise. Wide entry super late apex and stay on that side for exit to maximise entry to the next one which opens out onto a straight.