I"m sure this has probably been covered somewhere already, but I can't find it on these forums, and the info on the net is a couple patches old, so the percentages are different.

Basic synth has a 90% success chance. Steady hand boosts success by 20%. So depending how you do the math this is either a 110% total success chance or (20% of 90 = 18) a 108% success chance.

Yet I'm still getting quite a few BS failures with SH active. What am I missing? This happens on all of my craft classes so far, highest being lvl 29.