I think major part nung blues tone is how your pick or bare fingers attack and mangle the strings. Just because you play a Lucille ES-345 through a tweed Bassman doesn't mean you'll sound like BB King. neither would a Custom Tele through a Fender Quad Reverb turn you into the Iceman (Albert Collins).
sir delta question lang po: if it really is in the fingers, does it mean innate sa player yun, something that he is born with or it can be learned?
if it can be learned, any tips para maenhance ang "tone in the fingers" 
thanks
please allow me to "poke-my-fingers" in your pie, but not speak for Deltaslim coz i also want to know his sage insights on this. it just happens that we share the same flaming passion for this subject.
I feel that as people have their individual characteristics, there are certain "innate" qualities that are revealed when you play. What you do with the strings is different from the next guys. i dont think that you are "born" with talent (as you are not born with the guitar sharing the womb-space), but you can develope as a player. all things can be studied and learnt with the goal to make techniques "reflex" in action, second nature in execution, like speaking.
listen to what you like and who you look up to. immitate. focus on it. ask questions, to yourself and others. identify and dissect the fragments from the whole and try to understand it. then, make it a part of your vocabulary. listen, practice, listen, practice. search within. then forget about it and move on to immitate another.
its just like learning new words or phrases. you'll need to study, and when you encounter a new word you seek to understand its meaning and application. sooner or later, it is absorbed and comes out unconsciously in conversation.
for example:
my fave guitarist at the moment is brett garsed. upon hearing his music, i found some of the things he does very new to my ears, unfamiliar "words" and "sentences". i listen non-stop to his playing, research for resources available online (i even joined his fan forum and got a response. sweeet!). then i try to mimic what he does, and in doing so, i'm not exactly copying him but emulating him. that way, i filter his style with my own personality. i pay attention to how he attacks the strings (picks mostly above the neck pick up and uses hybrid technique), his fretting technique (four note per string stuff, skips, etc) his dynamics and lyricism, and the "rhythm" he uses in soloing. lately, i found that the "words" i lifted have gradually been absorbed in my vocabulary bank, now a part of my personal system.
don't be afraid to be "unconventional" about how you do things. you have more to fear if you've frozen to become a mannequin of your hero. there is nothing wrong with simple "immitation" though, as humans have always immitated each other, like children immitate their parents gestures and music itself serves to immitate (as the blues immitates crying, the bark of the dog or the roar of the train). but immitation is just a beginning, a trampoline to get you off your feet by bouncing up. in time, your maturity will lead you to discover yourself inside the instrument, and the tone will be there
