In reply to Inchewan:
I'll chime in again.
I'm not trying to be confrontational, but it does seem as if you have received numerous diverse and useful responses, but you're still searching for something more, some kind of specific answer, when the gist is, "There is no right answer, do what feels good for you." You also seem to be responding to each post with a manner that's not quite defensive, but almost dismissive, as if to say, "Yes, I know that, but what about this (further situation)? So I guess I don't really know what you are looking for; do you want an answer for a specific situation? As above, I think the answer is that there is no right answer. Do you want a survey of different responses? You have received lots of good responses already....
OK, with that out the way, what about the situation you describe?
"So what safe techniques do you use when you are on middlin steep slopes of around 45 degrees, on hard pack snow, unroped, using alpine 60 cm axe. In theses conditions the spike will only just penetrate the surface up to an inch or so. Do you use pick in, pick out, pick and spike in, hold the head of the axe, hold the shaft of the axe, with a leash to harness, with wrist loop to axe, or leashless. All this in combination of appropriate safe crampon techniques. Common examples would be on an alpine PD route."
If I was on a 45 degree slope that was so hard that the spike would only penetrate a inch, I would consider that ice climbing. If I could not plunge the shaft deep into the surface, or if I really needed to swing the axe from the bottom of the shaft to get the pick to stick, that's low angle ice climbing. If the surface is really so hard that the spike will not penetrate more than an inch, then holding the axe high on the shaft near the head or on the head with the pick facing forward isn't going to do anything; If you tried to place the pick from either of these positions it would just slide sway. And of course self-arrest on a slope like that would be incredibly difficult. So the only way you could use the axe is as a simple balance point (and nothing more) perhaps in combination with a trekking pole.
On that kind of terrain I would look down, and think about the run out, dangers like crevasses, cliffs, rocks, and so on, and I would look up, and see if the terrain got steeper above or leveled off, and how long the 45 degree section lasted, and what the conditions looked like just ahead (for example much softer snow visible a sort distance ahead). I would also think about how secure I felt on my feet, with whatever techniques and tools I was using. Basically, I would think about the consequences and likelihood of a fall.
Then I would put that together and decide whether to continue or change tactics. If I felt solid and it was just a short distance to safer terrain, I would probably continue, using the spike as a balance point, holding the axe with the pick forward or back, whichever felt more comfortable and supportive (and therefor safe). I wouldn't worry about self-arrest because it would be impossible. I would not use a leash, because, for the reasons mentioned above, I think leashes of any kind in most situations are useless, provide a false sense of security, and complicate movement, and are therefore potentially dangerous. To answer your previous question about leashes (paraphrased) "How do you keep your axe from sliding out of your hand?" by holding onto the axe with a strong grip and using good gloves.
All that said, if the 45 degree ice slope continued for any length, I would probably out on a harness and rope and start climbing together with a partner and a running belay. Putting on a harness on a 45 degree ice slope, and dealing with ropes and gear would hard and dangerous, so I would be sure to anchor myself first with an ice screw and kick/chop a small platform. Then I would climb, again, using whatever technique felt most comfortable and safe, either standing up and walking using the spike for balance, or facing in and holding the bottom of the shaft and swinging my ice axe to get real pick placements. If I encountered this terrain on a descent, I would probably face in and down climb, maybe with a running belay or a real belay.
I think it's important to consider that a 45 degree ice slope, while perhaps easy enough to walk on, is not a place you want to fall. One trip and you can break your ankle, to say nothing of falling with no chance of stopping.
If I have miss-interpreted you scenario, and you were not imagining the slope to be quite so hard (ice) well, then, see all the responses above. If you can plunge the shaft or place the pick from any hand position near the head, just do what feels safe and solid and smooth, for you.