User blog comment:Stpehen/Level up! Grenades level 30!/@comment-1917218-20101119015431

Here's how i mastered 'em.

first, get to level 20

retrain and put a point on everything then put all extra points on the bottom skills. determination, demolitions, ignore pain and toughness.

Then while using grenades, keep switching between fire, stink and smoke. BUT only do smoke when the previous smoke runs out.

with urchinfists and a crew bonus with another account, you can get an easy 70-90 rep.