I think one must not remain static, I mean, if one wants to try something new like a new martial art one should go for it, it can't be wrong to try new stuff, besides it can be fun and cahnces are one can learn something new.
I did crosstraining in Kenpo karate a few years back, it was possitive, I knew new people and also learn new stuff.
Empty the cup is something very difficult to do I already know, because mind,body and spirit have one way of doing the things, I can remeber one kenpo class where the sensei teach us three or four techs and at the end of the class sensei ask us to prearange a self defense sceanrio where we can use the techs learned some minutes ago, so I revieved the techs on my mind several times and when I feelt ready I ask my classmates to perform the atacks from 4 distinct ways, in a hurry defende myself BUT I use my TKD techs to do it, the sensei gave me a smile and told me I defend myself very well however I did not use any of the kenpo karate techs he taught me, I was a little embarrased for these, yes I defend myself very well but not using Kenpo. That's why I tell you that empty the cup is so diffcult.
Manny