Well, guess I'll be the first to state it (and that IS tremendously sad) but your guide sucks.
It might decieve potential good players into playing dec sin in pvp, enlarging the list of useless and nonskill assassins. No, seriously, it is not about diversity of choice, it is all about effectiveness, and playing pvp dec sin is like playing combat rogue in 3v3 WotLK arena: pointless, not effective and completely dumb. With such build you won't be effective in pvp (crappy survivabilty and lack of key pvp darkness perks such as FP) or pve (gratz with 5 wasted and ineffective talent points in context of pve dps maxing). Honestly, with that build you'd be effective only in sandbox with underschool kids as opponents (and I wont' bet my money on your victory even there).