Jiujutsu is one of the most common bushi skills, and is trained in dojos in many schools of many clans.
However, as it is the art of unarmed combat (or with improvised weapons, but I think this part is less taught by senseis), it implies inevitably unarmed hits/demonstrations among students. So direct physical contact.
However, in the 4th edition rule book, on page 32 it says the following about touching:
Samurai also do not touch in public unless required to by circumstances (e.g. catching someone who is falling, helping up a comrade on the battlefield, treating an injury, and so forth). To touch someone without absolute need, and especially to touch someone in a formal public setting like court, is a serious breach of etiquette.
So how does training work? As it is simply training, I don't think we can call it "absolute need". But most training implies one sensei and, often, many students at the same time. So the context "in public" applies here.
So how does it work? Do they only practice dodging? Do they use lower-rank people as fake adversaries?
Or does the training only consist of theory and repeated movements in the air?