I wouldn’t say it ruins it for me, but in the time taken to analyse a line to see how it to make it work better, running at maximum speed so the trains get around enough times to see what is happening, decades can pass and suddenly it’s time for another round of bloody vehicle replacement again. Other games, such as Civ, let you adjust this factor.
Quarter the time taken, quarter the costs and revenues; but bear in mind that this may mean waiting four times as long for the time to pass towards that new vehicle type becoming available or having enough money to build new routes. My PC is fairly fast, but running at 4x definitely sweats the processor; and when there are a lot of objects to simulate, I think 4x is not really 4x faster – it just goes as fast as it can to try to approach that. Don’t underestimate how much is going on under the bonnet (hood) in TF. You may find that 4x is as fast as it can go unless you have your own supercomputer. Personally I wouldn’t mind this too much, but it has to be balanced. We want more time to study and perfect our lines, but we don’t want to have to wait for ages to accumulate enough capital to build the next stage of our network because the maximum running speed can’t exceed 4x.
A word from the devs would be good here: is the 4x speed limited to 4x because that’s as much as a typical PC can manage? Is work being done to optimise the processing so it can run faster?