I own a Violin, Guitar (I want to play Slide Guitar), Trumpet and Piano obviously, all acoustic.
Piano is my primary instrument, like I have said on other posts, I practice about 3 hours a day on average. But after so long, I reach a point where I can only take so much of a piece(s) at once (learning Hungarian Rhapsody Number 5 and other Liszt pieces, I plan to record a Liszt EP in the future). I also learn a bit of Jazz along with the Classical (Hugh Laurie and Ray Charles stuff mostly, but also some older stuff, like Autumn Leaves). Also I can only play the piano so late, but I can play all other instruments as late as 9pm or 10pm.
I practice Piano before anything else. Then Violin for about 30 minute to an hour. Then the same with Guitar. Then the same again with the Trumpet. So sometimes I practice music pretty much the entire day (the rest of my time taken up by socializing, art, ATTEMPTING poetry and watching documentaries, I like Science) <- Kind of irrelevant, but just in case you were wondering. School has not begun yet.
Anyway, my question is, will my interest in these other instruments (Violin/Pizzicato for Romantic music, Trumpet and Guitar for Jazz) damage my Piano ability/progress. Give me an honest answer, because I have been told by some people that simply practicing Jazz on the Piano as a Classical pianist, can chip away at your Classical performance.