I like to think I'm quite a good guitarist - I'm very solid rhythmically and have a good ear for music - but my weakness with maneuvering my little finger is killing me at the mo.

I'm heavily into country and rock 'n' roll which of course draws from the blues progressions. I find it pretty much impossible to lay down the 'power chord rhythm'.

For example, in the key of A, using the little finger to play a 9th fret note on the A string every other beat as part of the A power chord. (Best way I can describe, I'm sure you know what I mean! Listen to the rhythm backing for a track like 'Roll Over Beethoven'!)

What can I do? I do practise relentlessly, btw. Can't help but feel I'm limited by having one of those weird bent pinky fingers!
In all probability your answer is in this video:


However, without seeing you play it's impossible to tell with any certainty what is actually the issue.
R.I.P. My Signature. Lost to us in the great Signature Massacre of 2014.

Quote by Master Foo
“A man who mistakes secrets for knowledge is like a man who, seeking light, hugs a candle so closely that he smothers it and burns his hand.”

The thing about Little Finger is that he wants to exert power over Westeros, but doesn't have the courage to accept the visibility and publicity that come with it.

Also do pinky exercises with a metronome.