I generally use Shadow Strike twice against bosses, and for a big boss like the BC mainframe, I can probably get three in, maybe even four.
Fade->Shadow Strike->(do stuff during SS cooldown)->Ghost Walk->Shadow Strike.
During BC mainframe, I'll generally have time enough to do a second Fade as well, even with it's long cooldown. It seems like I generally kill it before I get a chance to do the second Ghost Walk, but I could be remembering incorrectly. I'm not one of those people that does BC ten times a day. I haven't done BC all that many times, and not in a few days.
Be careful with this attack sequence against ordinary mobs, as they will often reset after a Ghost Walk.
I'm not sure what the OP had for Secret Charge as I can't get the link to work, even if I click on the "Yes" button to switch to the old hashtag algorithm. However, I do have points on Secret Charge. I don't recall how many. I had a link for my own SW build, but I seem to have misplaced it, so I'll have to recreate it next time I'm in-game.
Some people like Ghost Walk and Blink for PvP as well. Ghost Walk never seems to be all that successful to me in PvP. It may be that I need to put more points in it. Blink takes to long as a user to set up, in my opinion, but if you can do it quickly enough to get out, then use it.
Server: Andromeda - Faction: Royal Guard - Guild: Guardian - Name: Balina