DF :
Each version is guilty of genuine frame-rate drops too, especially when traversing main roads in The City. This manifests more aggressively on Microsoft's platform, where drops down to 20fps are possible, as compared to 25fps on PS4 - but in amongst the frame-pacing issues this is trivial. The stimulus seems to be interactions with multiple guards, and travelling at high speeds around the game world - neither of which are necessarily the core tenets of a stealth game. In either case, the PS4 version technically holds steadier at these particular stress points, but the end result still appears choppy.
As a frustrating aside, even the game's pre-rendered cut-scenes have performance issues. Drops down to the 25fps range are spotted on Sony's platform, whereas the Xbox One shows up with frame-pacing stutters. This is easy to pick out even on the reference PC version (where performance is otherwise 60fps), and is most likely a result of further inefficient background asset streaming. Fortunately, Thief's install directory on PC shows us that there are only six of these cut-scenes to worry about though.