Cross-training for grappling

[Cross_Trainer]

Right now I have been doing Goshin-Jutsu karate for about eight months, and I have a few questions about the two cross-training options in grappling open to me, which are: Judo and a (non-Brazilian) jujitsu/self defense class split. Both are taught by the same schools on different days. My questions for you are:

1. Are the movement patterns of judo, jujitsu, and karate relatively similar, and therefore not likely to screw me up by confusing me about which style of movement I should use with this or that move.
2. Will it retard my training if I take one of these in addition to karate? (I have enough time to get all of the classes in for both)
3. Should I wait longer before I start cross training?
4. If so, how much longer?

Thanks for your help!

[HiryuHien]

well that depends on the instructors and the way they teach.
now jujutsu(the kind similar to Daito-ryu or Yagyu-ryu classical) is similar to some of the grappling used in certain types of karate when you control a limb and use a lock or a strike

judo i know absolutely nothing about. i wont comment.
but I would say as far as grappling, jujutsu would be a very effecive addition to grappling for training

and being that most MA have similar base principles you should be fine
the little jujutsu training I have had enhaced my karate and showed me that evading and controlling is more efficient than blocking...

are you going to compete?