It is one of the main routes by which inconsistency and incompatibility entered.
If LBB:5 added military options to LBB:2 fair enough, but it didn't.
Different TL paradigm, different outcomes when designing the same ship, LBB:2 ships that don't meet LBB:5 requirements
(TL9 jump 2 scout, TL10 jump 4 xboat)
It is inconsistent with the LBB:1 and LBB:4 combat systems. It is only compatible in describing the same weapons and them killing characters, the devil is in the detail.
There is, which is why I ask how does the article explain drop tanks and the particle accelerators? It doesn't. What is a heavy laser that you treat the particle accelerator the same as?
So not the same...
Lol, don't get me started on the differences between 77 and 81

Suffice to say there are bits of 81 that are inconsistent and incompatible with 77.
I wouldn't still be playing the game, and talking about it, and recommending it, if I didn't feel the same way.
But Traveller has always played fast and loose with consistency and compatibility, It is one of its endearing qualities to me.