I've used Small Block Chevy V-8 offset crank cam gear keys in 261's and my current 302 GMC.These are custom one off cams that needed adjustments to fit the situation.
Generally speaking,a few degrees one way or another won't make a difference in a mild street engine,and adjusting the cam a few degrees won't turn a pig into a thoughbred,But you should always degree in a cam just incase the various "tolerances" of the parts stack up wrong.