I realise that this thread has been gone for a little while but I thought I might post a reply anyway.
As a white belt myself, I was absolutely dumbfounded to find that I benefitted from having a complete beginner (first lesson) pairing off against me.
My teacher told us in that particular lesson that ikkyo is one of the most important exercises in Aikido and to do it properly is very difficult. I must say that my ikkyo, while appearing correct to me has never felt 'right'. I found that by practising with this complete beginner and trying to help him understand the movements, I gained a much better insight into the reasons and timing of the movements. I am sure that when one starts off, little revelations come quite frequently as you 'get' a technique, but this was still an incredible feeling and I bowed very long and low to my partner after training.
I think that recent starters in Aikido may have reservations about training with complete beginners as they want the best guidance possible, but training with this guy, I was forced to analyse my technique. Never a bad thing - especially for a beginner.
Please - everyone thinking of starting Aikido - just get in there - we need more!