I would guess that the mast bending characteristics should be more or less in accordance with the load on the luff/halyard. If you modify the system, the mast will be bent back less or more, probably not desireable? Also, if the halyard is not in a rail (for example an a H16 you would have to run it outside the mast), if the mast is bent back, the distance from top to bottom gets shorter and thus the halyard tension would decrease.