Internally, Arc was still reeling from the shock that his initial attempt at condensation had resulted in. His lungs had been filled almost to the brim with the liquid that did not displace air, and he felt like his lungs were on the verge of exploding before he had coughed it all out.
It should be known that Xan in a condensed state wants desperately to repel from itself and turn into a gas. That same repulsive effect that he had trouble with while moving a single drop through his internal paths was felt on a far greater magnitude when almost a bucket of it was in his lungs. If he was in his physical body there was a very real chance his body would have exploded. He definitely would have wound up dead. The only reason he didn't faint on the spot was the protection from the Astral Field and his experience with the literally soul-ripping pain of that soul formula Zerrin had given his father to feed him.
Although he was annoyed that Bell did not give him any warning about this, he recognized that this was done for the sole benefit of his safety. He could guarantee that without this experience, that is the first thing he would have done upon his return. His first breath of Xan would have also been his last.
Of course he had no idea that the natural levels of Xan down there were not even remotely close to the level Bell had put out on a whim. He was even less aware that the danger was not the threat of him literally exploding, but of toxins and imbalances forming at a rate faster than he could expel and compensate for them. However the point got across flawlessly either way.
"Don't do that shit ever again."
However even with this shock and numbing pain, or rather because of them, he was especially interested in how to do it properly.
The technique Bell taught him was fascinating.
He was to absorb the slightest amount of it from his skin and internal membranes like his lungs, mouth, and throat, at a constant but slow rate so as to make the concentration of it in his body the same as the surrounding atmosphere. From there, he had to slowly condense the Xan that was located in his focal points and slowly move it towards his nexus. The important part was to not condense it until it reached the points and not try to draw it in too quickly.
The idea was to use Xan's self repelling force to have the Xan 'push' itself in to his less Xan dense body. Once it was pooled in a focal point he could slowly condense a bit and isolate it from the rest of the repulsive force, drawing it through his isolated pathways towards his Neidan. There, it would 'soak' the neidan and he could use it to develop and grow.
It was important to draw Xan in SLOWLY as that same repulsive force could wreck havoc on his body should he absorb it too fast. The reason for this had to do with his pathways and focal points. His paths were made to isolate Xan from the outside, meaning that it is able to act on it, but that also means that Xan is capable of exerting force onto THEM as well. Should he absorb it too quickly and the flow of Xan becomes too much to handle, the internal tearing caused by his paths being torn apart and ripping flesh may very well kill him, if not cripple him.
The focus points were vulnerable for a similar reason. Their whole existence was to draw in and hold Xan. Therefore they were very tricky to use while absorbing Xan that was not controlled. While the paths were isolating from both within and without, the focal points are only capable of isolating what's inside of them, albeit much more effectively. The trouble comes when any Xan that is not controlled by him and is still subject to forces from Xan OUTSIDE of the point. If the concentration of uncontrolled outside is greater than that within it, there is a chance that the point may rupture should that force become too strong.
Therefore it is vital for him to absorb evenly and constantly to avoid that issue.
In short, the three most important things to remember are to absorb slowly, constantly, and evenly.
Of course this doesn't mean that the rate that he absorbs will remain constant forever. Bell made it clear that the rate of absorption will increase drastically as he advances as his paths and points become stronger. She even hinted that there might be a point where he gets strong enough that he won't have to worry about it at all and simply mindlessly absorb Xan and focus on other things.
That was the biggest boon of this technique besides the quality gained from the marinating of his neidan in a constant stream of Xan, the ability to focus on something completely different while doing this. Bell stated rather matter-of-factly that this would be of amazing assistance in combat when he got more skilled in it as he would have a constant influx of Xan to work with. Pretty much every other technique required absolute focus on it to avoid damage the the paths and points.
Arc was the most surprised at the fact that this technique had no name despite the obvious time and work that went into refining it's concepts and process. However he thought that 'Origin Technique' was a good fit if what Bell said was to be taken at face value.
"Now give it a shot. Remember to first find the maximum flow your points and paths can take while you are still protected by the Astral field. From there practice at around a quarter of that rate in order to familiarize yourself. Until you get a lot stronger I want you to only cultivate at around half of your maximum flow to help prevent you from being injured by any sudden fluctuations in the levels of Xan. You have to remember your body is still that of a baby's."
It was with this that Arc found out why others might modify and abandon this technique. The rate at which you were able to cultivate was ultimately outside of your control unless you were powerful enough to withstand your environment. You would also be limited by the resilience of your body. Both of these factors vary wildly upon person.
Arc was confident he could handle it without too much issue.