Perhaps it would be good to make a distinction between aikijo and SMR. I study Shindo Muso Ryu right now in Japan, and studied a fair amount of aikijo in Japan. SMR is amazingly aikido like, (or vice versa.) Facing an opponent with a sword you show a massive opening, then use nonlethal techniques to demonstrate dominance, and the swordsman leaves with bruises at best, or okay maybe a broken bone. The point being that the movements are very much using the Jo as an extension of non-weapon responses to a weapon as opposed to the tit for tat combat that could be concieved of with the thrusting and blocking movements in many aikijo kata or paired routines.
In SMR the dominance of the sword as a weapon, (razor sharp steel vs. dried oak a few centimeters thick) is clear. In that respect it shares the same respect for life, in that even though you are supposedly attacked by the swordsman, dominance of the spirit and technique are combined with benevolence. Very aiki idea.
Aikijo is clearly a combination of spear, bayonet and some SMR ideas. Both are valuable to the aikido student. aikijo teaches excellent irimi vs. a long attack, and it is good for showing the fundamentals of extension. SMR is incredibly difficult, but will reward you with the ability and mindset to commit your hips fully into the art in question. It is a lesson in commitment to your opponent as well, risk all to make up for the disadvantage of stick vs. steel.
anyway, enough of my rambling. If anybody has any specific questions, I would be happy to ask my teacher.