Also worth mentioning is that you don't always know what outside training might *inform* your practice. I stand in rooms around the world almost on a weekly basis with30- 40 people ( including shihan) from about every major discipline out there from MMA to Aikido all working on a method no one knew would have EVER... as you say... informed their training, contextually or otherwise as most didn't even know it existed.
Which leads to your other point quite nicely.
Context
Context is interesting as well, as lacking prior experience in any other given field outside your own, it may sometimes be only a guess that, "that stuff over there" would contextually inform your own training. So who, really knew best. Oops I forgot it's the age of the millenials... Of course each person knows best what is best for them... Cough.
I can think of many different disciplines informing others, hence why I have done MMA from 14 yrs old. Then? Few were combining wrestling with judo with karate and boxing only to have a Philipino guy show up one day with sticks.
In the right hands? It's all good.
I think by default it is better to assume you can learn from outside. Sure you might not want to consider training in Itto ryu and KSR at the same time as your body is going to get confused, but there are many arts that will inform and compliment others.
Dan
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