since you only get +1 to a skill on Cotw'S , you need strong 1-pointers for them to worth (think at melee barb or holy melee main attack skills as example - or buffs/passives/stances)
1-pointer elemental spells (fire bolt nova in your case) are generaly crap since you would need them maxed or smaxed in order to deal decent damage . the exceptions are very few (1-pointer Flamestrike as example for those exceptions - it deals decent damage even as 1-pointer)
you can also check the skill calculator and see if the possible output damage of the 1-pointer you got is good enough for our needs / if it worths the trouble .
http://dev.median-xl.com/?script=skillcalc . i am not sure if the tool is up to date as i don't normaly make any calculations with it , but i believe i have red somewhere that it probably shows higher damage values that what you realy get in reality . if someone knows more info here , please correct me if i am wrong .