Więc cytując owóż forum, można inaczej:
(Pure speculation alert)
If (and ONLY if, IMHO), the whole BFR idea was found to have some show-stopper faults and SpaceX had to perform a massive re-trenchment and re-thinking of their goals, then they might have to compromise on their vision. Faced with years ahead and needing to maintain their commercial position, while still heading for Mars, perhaps something like this:
Bite the bullet and give up road transport and McGregor testing of whole stages.
Take the work done with Falcon X (although I think they had barely started), and create something that could replace Falcon 9/Heavy in the next decade. Maybe take another look at cross-feed, since they're building a new rocket. The result: 6 meter diameter bodies with 9 Raptor engines each. At current projections: that would give the Heavy a SL lift of 10.2 million pounds of thrust. Ground operations would be just like the well-proven (by then), FH system, including barge landings for the core. With cross-feed, the aim would be for a higher velocity start for the second stage.
The second stage would be a smaller version of the BFS and be re-usable. Perhaps 7m diameter? It would come in the same three flavors.
The family would be called Falcon Super and Falcon Super Heavy, thus keeping my post on-topic!
(End speculation alert. I wouldn't want this to happen, but I think it would make a lot more sense than trying to put five or more Falcon 9s together. Crossfeed and the outlook of many years before something like BFR/BFS could actually be built would be the only reasons to go down this road. My fun 2 cents.)
Really, FH brakuje raptem ok 20% nośności, żeby dorównać SLS. Możłiwości są. Jeżeli Musk ich nie podejmuje, to nie dlatego, że to niemożłiwe, tylko dlatego, że uważa, że z BFRem zrobi coś niewiele dłużej, a dużo lepiej i taniej. Dokladnie to samo podejście, któego brakuje w NASA: nie ładujemy pieniędzy w projekty nieperspektywiczne, bo pieniądze nie rosną na drzewach. Asygnujemy je do projektów, które dadzą najlepsze efekty w dłuższej perspektywie. Nie przepalamy majątku całej firmy, bo ktoś koniecznie chce udowodnić swoją przydatność i polecieć na księżyc za 5 lat no matter the costs.