Interpolating unconnected situations and events into a narrative does not harm the conclusions. For example, we could put situations S0.5 and S0.7 between S0 and S1, and suppose that Junior reads a book on the airplane during the inner interval. The previous statements about what holds when Junior arrives in London should still seem ok. Indeed we have that when we add
we can conclude all our previous sentences, plus some more about Junior's intelligence, something we earlier did not have an opinion about.
In our second narrative, after S2 we have two possible explanations
of how Junior gets the cash to buy his ticket. One explanation is that
Daddy always gets cash to Junior. We also have the more detailed
explanation that Daddy sells 
and sends the proceeds to Junior.
The more detailed explanation is an elaboration of how Daddy got them
cash to Junior. If is worth noting that both explanations can
co-exist in our narrative without inconsistencies.