Both are Possible


Here’s the video. Although the launcher is familiar, I doubt that three engines will be able to work, as the centre engine will have enough thrust to land. A boost-back burn is demonstrated.



What is your criteria for “too much thrust for landing”? I don’t know of any theoretical upper limit. Higher minimum thrust and acceleration make landing more difficult, but it’s not impossible.



Theoretically speaking, when thrust increases to infinity, the vertical velocity will also decrease to zero. The titan launcher In a real-engine, there’s a certain minimal time for startup+thrust+shutdown. Particularly when the turbopump is involved. The stage dry mass is the ideal source of landing engine thrust.



Aside from that, considering we’re likely to be contemplating an F-1 that weighs 100t or more, the engine is likely to be bigger than the F-1.



First, F9 can use 3 out of 10 engines. In that case, landing on just one of 3 engines doesn’t appear to be at all extreme.



Second, if you’re going to posit an engine with infinite thrust you can also imagine an engine with infinitesimal start-up time. Both are possible. Both aren’t even close to what is actually relevant here.