They would help as expected even though they would do exactly what you expect them too - take up the crank ends pivoting and tipping binding inside case races. What will nullify the above function is the crank bows like a jump rope so one can run into binding in rod journals and the things attached to end of crank like cam and oil pump getting snatched apart and alternator rotor abraiding and melting inside of stator. The stiffer superblends may help rpm some by resisting the crank flex in the middle - some what better than if end free to trace an squashed cone in air.
Spherical swivel bushing in my Pachymayer .45 acp allowed barrel freedom to gimble to cycle freely yet lock up solid no slack at slide slams home and big bang goes off. Very smooth no vibration action with blunted recoil that gave sense of it being the Commando of big bore pistolas.