On the other hand, ISS was designed for low earth orbit. Period. Adapting it for someplace else would cost so much you might as well build a new station. The radiation environment is different. The thermal environment is different. The ISS’s resupply needs are also a problem. The first long term habitat for humans in deep space will have to be purpose built, since moving the ISS carries too much additional risk. Its hard enough to do new things in newly built hardware By the time human occupied deep space stations are proven, the ISS will likely be at least a decade older and still in its present location. Or it will be taken apart and used on other LEO stations.

Scott Manley explains the use of these strange or unexpected routes to the Moon.
https://www.youtube.com/watch?v=WVrWcbyOmxY (14 minutes)

It seems that with computing power at the level we have these days, we don’t necessarily have to solve the three body problem (or, in this case, a four body problem: Earth, Moon, Sun, and spacecraft*) to find new and unusual — but useful — orbits. Manley does not have an example of using the Moon in the way Robert described: slingshot the probe with the Moon to send it back to the Moon. This may be a first.

Notice that these strange orbits take weeks and months to reach the Moon, rather than the three days that Apollo missions took. The advantage is that less propellant is required; the disadvantage is that more time is required.
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* The two-body problem is easily solved. It is a simple inverse-square law solution that results in elliptical orbits. The Lagrange Points are a specific solution to the three-body problem, and as Manley shows, it is not a simple solution, but has some locations and concepts that are fairly easily understood.