I have been using 7lb dumbells working on the jab and can honestly say that I think it has really helped so maybe just work with them on my lead hook as well. I feel that I need more speed in releasing both my body and hand through the punch. I know Roach also said that he would have swapped his cross for a better lead hook and he has a mean lead hook.
Maybe I should just switch to southpaw and work on my left cross instead. HAHAHA, Seems easier