Experimenting with head position during push-off from the pool wall is a great exercise, as it will build the feel for which position is truly the most hydrodynamic.
In pool training I have a regular habit of marking the 6m mark (just past the flags), either by noting some marking on the pool floor itself, or placing a large smooth glass bead on the floor as break-out marker. This is my target for the push-off and break-out point.
My pattern, if using a Tempo Trainer, is to allow 3 beeps. 0 beep is the push off the wall, 1 beep is straight streamline, 2 beep is a slight body dolphin, and 3 beep is when I should start the first underwater catch, and at 4 beep I’ve broken the surface.
If not using a Tempo Trainer, I will still do an internal count to three to set the first catch. But I always aim for that marker on the pool floor to ensure I’ve done my best.
As intensity increases I will be more challenged at holding a long streamlined body to reach my marker. In a long or intense distance I notice most swimmers start the first one or two breakouts at what may be a nice distance for them, but then shorten up the breakout significantly for subsequent lengths. Examining the reasons why is important for each swimmer to see where we are losing focus on streamline or quality of the push-off or break-out. It may not be just about conserving energy on the jump, but wasting energy with poor body and head position as we try to glide.
At any intensity level using a marker like this can also be good for drawing your attention to anything that causes you to breakout shorter than your goal. The power of the push (how steady or how snappy), the depth at which I pushed off, how straight and parallel to the surface I was, etc.
And when I see that I’ve come up half-a-stroke short on the marker, I know this will mean I’ve already lost half-a-stroke on my SPL. So it helps me stay keen on every detail that makes a perfect 25 length.
The most annoying problem of using markers like this to help imprint push-off skill is that people (or kids) unfamiliar with my routine see my markers and pick them up, wondering what they are, or think it is a free toy to start playing with. So find something that looks boring to draw little attention but my own, yet heavy enough and big enough to not slip down the pool drain. (If you are a little naughty you might try making a little tick mark on the tile with an oil pastel crayon!)