Where I practice, the introduction to weapons training is staggered, tanto, bokken then jo, from 2nd kyu onwards.
I was very impatient to get to the weapons when I started, and I didn't understand why I had to wait. When I got there, I really appreciated the preparation I had gone through to get to that point.
IMHO weapons training should be treated with great respect. I'm not sure that a beginner in aikido has anywhere near enough understanding of the basic movements in aikido to do weapons training properly.
I watched a large gathering of different aikido groups last year and saw weapons in the hands of all grades, some of the weapons handling by the early kyu grades (tanto in this case ) was very sloppy. I can't say I was impressed, judgemental I know, but honest.
I'm not saying it shouldn't be done, but I think beginners to aikido have enough to deal with just figuring out where their feet and hands are supposed to go, let alone being able to extend their mind to the tip of a bokken and cut with any real effectiveness.
So although it's frustrating in the beginning, I'm glad I had to wait.