I voted no.
A thought: We want a strong and comited attack from our uke, but we never practise attacks in Aikido. The attacks are often, but not alwawys, lame (as many threeds here prove).
A former Karateka can throw a tsuki that is committed. An Aikidoka (who has no other martial arts training) can merely mimik that motion, with more or less success. For most of us, there is a difference. A real tsuki is not something every one does good automaticly. You need to practise it, not just mimik it. Otherwise you could learn Kung-fu just from watching movies...
Also, I find Aikido to be a bit harder to learn than other arts. Other arts use force, Aikido don't, and it's common that newbies compencates lack of technique with strength.
I find that my pre-aikido arts (judo and taekwon-do) has helped me a lot in my Aikido. I feel no need to "move on" to another art.
/Patrik