Maybe the fact that your normal routine, how much exercise you have and what you eat is making you more sensitive to insulin. I find that people try to keep their insulin intake the same all the time, but if you eat low GI foods consistently, or start exercising a bit more each day, your body becomes much more sensitive to insulin meaning more hypos and a lower dose is required.
It works the same way to, if you start eating more high GI foods that cause high BG levels, then you will become more resistant to insulin. It's the same if you start exercising less, like if you stop walking some where each day and drive there instead, you will slowly become less insulin sensitive.
I also find that my body works with my lifestyle, because I've had time when I was on 40+ units of levemir and 25+ units of novarapid a day and each day I got more and more resistant to insulin, because I was having high BG levels and not exercising. Insulin resistance seems to build on top of its self, to the point where if you are insulin resistant, you will become even more resistant if you don't make a change.
It also works the other way, after weeks of eating low GI food and exercising a lot, I had much better control of my BG levels and I only needed 16 units of levemir and 10 units of novarapid each day. After keeping the same diet, I realized that I was hypoing more and more, because my insulin sensitivity was improving every day. I am now at a point where if I was to eat the same thing that I ate months ago when I was taking 40 units of levemir and 25 units of novarapid in a day, I now would only require 5 units of novarapid and no levemir.
Even now, I know that my insulin sensitivity is slowly increasing, so in time I will need even less insulin. I don't know what the lowest dose possible is, but I know that people taking huge amounts of insulin can defiantly make changes to their diet and exercise so they don't have to take nearly as much and I doubt taking lower doses is because of honeymooning, rather you are just developing a higher insulin sensitivity.