you are talking like you are disagreeing with me about something, but I can't see what it is. What the grid is made of is of is irrelevant to its existence and effect on gameplay. It is specifically defined as containing the jump field so that it doesn't affect objects around the ship.The T5 hull grid is a network of cables of undefined material, as is stated in MWM's article. T5 uses lanthanum in the drive coils, not the hull network/grid.
And again I will mention that in the setting the megacorporations are doing exactly that in the core sectors and wish to expand this into the Spinward Marches, with local shipyards winning contracts to build the tanks. Many Marches "interest groups" appear to not want greater Imperial authority and megacorporation involvement.
I am aware of the storyline of drop tanks. I've been playing Traveller nearly as long as you have (I started in 1980). And if they hadn't wrecked the 3I, drop tanks would have radically restructured ship building and trade. Yes, starting in the Core and taking a moderately long time to reach the fringes, like most technologies.
The setting conceit that most ships are low jump is based around the fact that high jump requires a seriously constraining level of ship volume expended on internal L-Hyd tanks. Putting a Jump 5 or Jump 6 drive in a ship is not a problem. Spending 50 or 60% of your volume on fuel is. The increased fuel cost on jumps is easily offset by the additional cargo capacity (and the cost savings on getting the cargo moved on less hulls and fewer crews. Military ships would probably want some internal fuel capacity to avoid "the battle riders are trapped" syndrome. But they'd probably have J-6 drives and maybe J-1 or J-2 fuel for an emergency escape and use the rest of the free hull capacity for mohr dakka.
And that's fine if that's what one wants. The only thing I objected to is this idea that some other posters appear to be presenting that because drop tanks are defined in the rules as less than optimized at the moment, that it makes any sense to think they'd stay that way for long. They are, imho, that big of a game changer. No one's going to leave them on the not quite finished list for long.
Anyway, none of this has anything to do with what the initial question of the thread was about. And this is starting to feel to me like its shifting from discussion to argument. If that's my fault, I apologize. Regardless, I am not interested in arguing and I discussed my POV on the issue. So, ttyl