An analysis that I consider to be very important to the whole question of the sequence of events is Bruce A. Trinque's
The Final Seconds before Collision. Note particularly the testimony of Barrett, Beauchamp, Dillon, and Scott, all of whom place the noise of the collision as nearly simultaneous with the first order telegraphed to their work spaces - which by
all their accounts was STOP. The joker here is that Dillon and Scott were referring to the
engine telegraph, while Barrett and Beauchamp would only have been able to see the
stoking telegraph. It is significant to note that if an order to REVERSE engines had been received, the stoking telegraph would not have changed, because as long as power is required, steam would need to be produced. Therefore, the fact that the stoking order was STOP strongly suggests that the engine order was the same (and virtually simultaneous, because the engine crew would have signaled the stokeholds in the process of stopping the engines). The sequence of Murdoch's orders would logically have been:
Starboard helm (to start the port-around)
Port helm (to swing the stern clear)
(Collision)
Engines stop (to protect the prop shafts)
Engines astern (to stop the ship after the collision)
This sequence is corroborated by all the testimony that comes to mind, with the exception of that of Hichens, and Boxhall's recollection of Murdoch briefing Smith. But Hichens' confusion on the spacing of commands and collision might make his version of events suspect, and Boxhall places the crow's nest bells, collision, engine telegraph and helm orders as almost simultaneous, which makes the accuracy of any of his recollection problematic.