Maybe I'm extremely over-simplifying things but I decided to do nothing against birds, at least not when the required manoeuvre would make my aircraft look like a fighter jet. Here's why:
A bird can weight anything from 6 to 12-ish pounds (maybe more, yes), my aircraft weights 12.500lbs at full load. You people in the heavyweights have bigger masses. So the bird is lighter, hence it can manoeuvre more easily and with less effort and in less time as well
One way or another a bird has been flying for millions of years, since it is evolution what has allowed it to fly the way it does, hence it's got millions of years of experience at flying. Us? Well, we've been flying for a bit over 100 years and we were not "designed" to fly anyway, so we're out of our environment when we are in the sky.
So, if you are in a position where an "extreme" or abrupt manoeuvre is required to ATTEMPT to avoid a bird you are the least likely to make the avoidance succeed, whereas the bird can just twist a wing a wee bit and they can fly towards their intended direction with a little help from it's survival instinct. Even so, the bird weights just a few pounds, not thousands or even hundreds of thousands of pounds, so the required effort for the bird is much much less than your effort required to steer the aircraft away from the bird.
Trying to fly away from the bird can have big chances of coming across something similar to this:
The only bird we hit in over 600 landings there it was the FO flying and at 500 ft on take off we both saw the turkey buzzard in our path following our turn so we reversed the turn and the buzzard did too. We reversed again and the buzzard followed. The FO said they always dive so we pulled up as much as we could and the buzzard did likewise
I find it similar to when a car is about to hit you while you're walking on the street; the driver knows he has to dodge you and (regularly) will try to do so and he decides early enough where does he wants to steer. However, if YOU then try to get out of danger by designing your own escape you create a bigger chance for you to be hit by the car. The solution? Stay still and let the driver follow through his manoeuvre. Same with the bird/aircraft scenario; too close to the bird? Don't move, let it dodge you instead of you dodging the bird.
I agree, though, with avoiding the spot where the flock is if you have spotted the flock with sufficient time and distance to do so without a fighter jet-type manoeuvre. If the required manoeuvre is such that it would make you look all Top Gun, you're too close now and you should let the bird dodge you.