Ta.
74s beyond Poole to Hamworthy, Blandford, Wimborne, Furzebrook and Winfrith were not unknown, and no doubt van trains to Weymouth too.
On this sort of point, 74s made it to Salisbury - I myself saw all of 74001/04/07/10 there between 1971 and 1975. And one rumoured, unconfirmed, to have got to Dinton, not seen by myself.
My comment was about 74s and boat trains. A point about a 74 is they were only 315 hp at the rail, less than 420 hp of a 73 - 2x73 840 hp is a closer to 3x74 than 2x73. Putting out 2x73 on a boat train is not only unusual in itself - it was not a location where such luxury of traction stood around on hand, 33s far more likely, so no-one noticed when the first 33 failed and merely replaced by another one.
I have had a 47 on an Up boat train, but, it was a 33 from the Quat to Tramway Jn where they changed engines - it was actually booked that day to do that, heavily amended loco and stock workings because of engineering works (actually a Sunday afternoon / evening after the works ended then putting trains back in their right places.
It does prove never say never, but then, here we are, one solitrary example so far, which still means platform end trasnpotter wibble on the subject is grossly exaggarted.