Think of the engine room as a box. Fuel oil, lube oil, parts, sea water, various consumables go in. A turning shaft, electricity, fresh water, steam hot water and so forth come out. Everything inside that box is the responsibly of the chief. Everything outside the box is the responsibility of someone else. There are more things outside that box then you imagine.
It has already been pointed out that by law the captain is responsible for everything that happens on the ship. This isn't going to change any times soon. Responsibility and authority are two sides of the same coin. No master in his right mind is going to surrender authority while retaining responsibility.
I do think that the "command" model of management works poorly when dealing with something as complex as ship management I agree with Capt A that it requires teamwork and trust.
The Art of Dredging has a
good article on this here
As far as having a hot line directly from the chief eng to ashore, I have the chief email the port engineer directly but I have him "cc" me also so I can keep on top of what is going on.
I have dealt with several people who share your views with regard to captains analytical skills and so forth. It does seem to me that often the deck side has a better appreciation for what the engine side does then the other way round. A good mate makes it look easy.