In 1987, as a British Labour MP, I was elected to the Shadow Cabinet by my colleagues and was asked by the party leader to direct Labour's campaign in the general election of that year.
The election was to take place at the height of Mrs Thatcher's dominance and we were expected to do very badly. We duly lost the election but ran a much better campaign than expected; I fronted on television screens throughout and attracted a good deal of attention.
For me personally, this ushered in a golden period. I topped the Shadow Cabinet elections in the following year and was elected to the party's National Executive Committee - I began to be talked about as a potential party leader.
But by the time the then-leader, Neil Kinnock, had resigned, following a further election defeat in 1991, my star had waned.
Opponents and rivals in the parliamentary party had done their best to undermine me, and I was defeated in the contest for the leadership later in 1991. And the winner, a Scot named John Smith, had had the support of what was then a powerful phalanx of Scottish Labour MPs in the House of Commons, whereas my own geographical support base was extremely limited - there weren't too many Kiwis in the parliamentary Labour party.
I recount this personal experience of the political roller coaster as a reflection on what we have seen in New Zealand politics over recent months when the roller coaster has been well and truly in full operation.
We had, first, the "rolling" of Simon Bridges, elected as National leader only a couple of years earlier, and then his partial resurrection as Shadow Foreign Minister under his new leader, Todd Muller, who - unusually - came from nowhere and, as an unknown, put himself forward for the top job.
Then we had the resignations and departures from politics of Paula Bennett and Anne Tolley. The former, who had been Deputy Prime Minister, must at one point have envisaged still further heights.
And we are now faced with the publication of a new memoir by Judith Collins, a perennial contender in the public mind for the National leadership, (and perhaps again now), but never quite pulling the trigger.
Nor has the Labour Party been immune from such ups and downs.
Their travails over leadership until recently are still fresh in the memory. It is their good luck (or rather, perhaps, good management) that the one stable element in the political landscape is undoubtedly Jacinda Ardern - she is a fixture, and unassailable.
But others, as David Clark will no doubt testify, can "suffer the slings and arrows", while yet others will feel, perhaps, that a new day is dawning. Chris Hipkins, for example, seems to be forging a reputation as a "Mr Fixit" and as having "a safe pair of hands".
The one thing we can be sure of, however, is that the political roller coaster will continue to buck and roll - not that that is entirely, or even substantially, an unwelcome feature of democratic politics.
Public opinion is inherently fickle and can move around with surprising speed, and is all too likely to be pushed one way or that by media commentary. From one viewpoint, that creates an inbuilt instability which many would see as an unfortunate and unwelcome backdrop to what one might hope would be effective government.
But, at another level, the volatility of public opinion might be seen as what keeps our politicians on their toes, and is an essential element in a functioning democracy; it is surely preferable to the manufactured and immoveable public support enjoyed by a Vladimir Putin or a Kim Jong Un.
And it provides an incentive to our politicians to be upfront and straight with the voters and to "tell it like it is".
And it makes all the more remarkable the sustained popular support enjoyed over a long period by our own Prime Minister.
She must be doing something right!
- Bryan Gould is an ex-British MP and former University of Waikato vice-chancellor.