I have read that one of the requirements for a rifle and its bayonet at the end of the 1800's was that an Infantry soldier must be able to bayonet mounted Cavalry.

When the SMLE was designed as a compromise between an Infantry rifle and a carbine (upsetting everyone) but trying to standardise on manufacture and inventory, they had to design the 1907 'Sword bayonet' to be able to comply with the 'bayonet mounted cavalry' requirement.

Doesn't answer your question tho';.