Where does the day go?

OK - way too long since my last post. Any readership I might have had will have long since got bored gone away permanently.

But, as busy as I am - I just can't work out where the day has gone. (BTW thanks thespian for prompting this post)

I have a theory about one aspect of what seems to be counterintuitive time perception. It is only half-baked, so to give it a little time-in-the-oven as it were, I shall try it out here:

The question is: why does it that sometimes it can seem that you have been really busy for ages, but when you look back over such a period, it seems that time has flown by?

My theory is 2-fold:
Firstly, most activities that take up our time are mundane and so never get put into our long-term-memory as significant episodes; they just "merge" with hundreds of similar memories.

Secondly, is that what few exciting and different things do occur to us can only get fixed in our long-term-memory by relating the story to someone else.

Combining these two aspects, you realise that very few things are significant enough to be recalled as important episodes in our life, and that as you get older, this becomes more and more so. The few exciting things that do happen are well defined by retelling and so they seem very widely separated in our memories.

Now, when you look back you find that it seems not much has happened in the last year, and fun exciting things hardly ever happen, yet you are constantly busy.
Time just rushes by, and you just can't work out where it has gone.