voo is right... .means that with growing rr you can decrease acual skill. with rr1 39 stealth+11 from items give you 50 stealth
more than 50 stealth does not give you any bonus, same goes for envenom.
with melee skills its slightly different.... till skill 50 you gain base dmg, if you skill beyond 50 your base dmg remains the samen but you styldmg bonus will increase.
with casting skills its slightly different too, till 50 your base dmg increases and the variance decrease with every skilllvl and this goes on after lvl 50 too

Pop wrote:There's so many variations and differentiating opinions here it's impossible to know who's right and who's wrong and what the ultimate DPS Shadowblade is...

Already told you the best spec for 1.65 is Critblade, i also explained why... Not so hard to understand

Other people might have another preferred spec, still doesn't change the fact on which is better, for this version.