"Thats how you tell a R/R, never use 5 bolts when 30 screws will fit."
Apparently RR did quite a bit of research in the 1920's and apart from anything else they discovered that for any given joint, more small fixings were both lighter and stronger than the same joint with fewer larger fixings. The fact that it cost more, was to them irrelevant I suppose.
Also my dear old Dad was an Engine Fitter on Lancasters during WW2. These had four Merlins. Dad used to say that it was possible to identify a Rolls Merlin from a Packard Merlin without taking the cowling panels off, (or looking at the paperwork). Simply stick your hand up an exhaust port, preferably when the motor wasn't running!!, the RR engine ports were smooth, the Packard Merlin ports weren't.
cheers
Bill Pudney