About the on proc chance pvp trinket.

[learty]

It procs even when you don't engage somebody as in instantly after combat, also if you just hit somebody it procs too fast http://www.db.pandawow.me?item=102840#see-also it should have 15% proc chance look at the reference >> http://www.db.pandawow.me?spell=126708#used-by-item

[Титан]

not according to the rules