That's just as valid a fix and preserves the relationship that the DMs establish which is C->B is +2 and B->A is +2.
One has to the two corrections to change from 150 to 160. Only one correction has to be made in the table to match the text 150. Being a lazy lout I prefer making one correction over two
Well, that's fine. I just prefer the one that prefers the relationship between starport levels as that seems more important to me.
What if my planet is outside the habitable zone, is cold, and my hydrographics are frozen methane or the like. We know hydrographics doesn't always mean water. Now, you could say 'well, in theory someone could mine fuel from there' and I can't say it couldn't be done, but that's a long leap from 'I drop the hose in the bay'. I doubt many crews could mine the methane safely and effectively without specialized gear which most crews would not have.
Most of the Traveller books IIRC say that the fuel can be mined from frozen methane and other similar sources with the fuel scoops, hoses, and associated pumps. I'm fairly sure that somewhere in the ship's computer data files are the procedures on how to do the job, especially the small ships on the frontier eking out a living.
I try to imagine this, but cannot. You will have something akin to glaciation but it will be made out of frozen methane (around -300 F). So you land and you've got glaciers. If you are going to work outside, you'd need truly amazing heaters for your suits. More likely, you'd need some kind of vehicle with tool attachments. You'd have to manually cut the methane into small enough blocks, then somehow get them to become liquid (so heat them up some amount but not to above around -260 F) and get that liquid into the ship's scoops and into some kind of holding tank.
The methane might have soil or other contaminants and many other gases could have frozen by the time methane freezes so you may well have a lot of different substances in with your methane. I'm not sure that mess, by itself, would constitute 'unrefined fuel' in that it still is not hydrogen. To crack off the hydrogen, you'd have to either provide some input of energy or of other substances to react with the methane to break off the hydrogens and collect it. If you did this with a mix of soil or other substances in there (like other frozen gases), you'd have to be careful to avoid dangerous reactions (perhaps) or at least the contamination of the fuel. If you introduce heat, you might send the methane into a gas state which I'll bet isn't the most handy for the fusion plant so you'd have to then cool it in a separate holding area or compress it to a liquid with machinery.
This all sounds to me to be a lot more involved and a lot more troublesome than dropping a hose into an H20 supply.
Now, I'm not arguing about the fact the books may say that you can do it, but I suspect that's more a concession to gameplay than a reasonable imagining of what the complexities could be and how likely any given small freighter is to carry this kind of gear to make that workable.
Then again, maybe I'm wrong. There could be some magic technologies developed between TL-9 and TL-15 that just makes this not an issue. I just can't imagine what they'd be or how they'd work.
TomB