I have a horde pally weaponsmith that has been maxed on basic skill and every skill tree. I only have 37% insp when making a 447 item of any kind (and that’s with a finishing agent to boost inspiration!). If I use an Insight on any thing with a missive and an embellishment it’s useless as it doesn’t guarantee a 100% proc.
It has always been this way since my skills were maxed… I have no idea what your comparison to BS is about as it has always been this way for JCs.
What bothers me is that some professions can 100% guarantee max ilvl items while others cannot (see my post HERE for screenshot examples/discussion).