As stoianm demonstrated in one of his video tutorials, it's possible to get away from the "X" (the location from which you fired the torpedo) in time, but you have to attack from a great distance (I think he attacked 5000 meters away from a carrier surrounded by destroyers) and try to avoid doing a fast 90 attack.
I'm not sure which version of IRAI he was using at that time, but I suppose his approach could work even today. Check it out, I think it's the tutorial on manual targeting + real navigation.
Personally, I think that the way IRAI works when you add the IRAI upgrade and the depth charge disturbances mod to it is satisfying for now, though unrealistic from the technical side of the story (the fact that the destroyers know your exact location). Combined with the disturbances mod, stoianm's tactics have worked for me on several occasions.
Still, I'm looking forward to seeing TDW working on IRAI again.
