Pardon the analogy, but bringing up Q_engineering in this context is like someone shopping for a car running into Ford's engine design department and complaining that the engineers are not using the car's fuel economy to increase the engine's performance.
How much power the subsystems takes has no influence on the plasma's performance. How much power goes into the plasma (and what type of power and where and when, etc.) do influence the plasma's performance.
We (now) know but most people don't, when somebody says it'll "produce X amount of power than you put in" any normal human being would think "it's done" but then they'll wonder for next X decades why there are no power plants yet? Because nobody told them that you need more power than it produces at the end and positive net was just for final reaction and without heat to electricity conversion.
It's tough to say because the campaign is a signpost on the way to an eventual end goal. But the end goal is easy to describe: "a working fusion power plant."
The end goal is so far away at this point, not a single player in this space is even trying to do it, even on their farthest-out roadmaps...
No, the campaign's goals were to push higher plasma energy out of a JET pulse. This required upgrades to many subsystems and to dust off everything necessary for nuclear operations.
They did this in support of ITER, but there are also likely other political motivations. There has been no nuclear MCF operation on Earth in decades and now the UK has invested in resuming theirs rather than mothballing it.
You can't make claims about the motivations of the campaign (such as it being a signpost?) if you don't know what was even done.
And again, you shouldn't talk about the roadmaps if you haven't looked at them. Look at PPPL FIRE and power plant studies.
Clearly the end goal is to beat the First Law of Thermodynamics and its pesky "conservation of energy." We already know how to print money, now it's time to print energy! /s
When you are comparing across different fusion techniques, which we implicitly are in our brains (because we are not sophisticated plasma physicists and not every strategy right now is magnetic confinement), Q_engineering is important to think about: different strategies will have different capabilities of harvesting the energy and turning it into power, and maybe some of the strategies (laser inertial confinement cough cough) are super-unlikely to ever have reasonable and efficient capture strategies. It would be nice to have an "estimated Q_engineering" come out of these experiments, even if they are wildly overinflated and crap estimates (as long as the assumptions that go into that are recorded). For that matter, it's not entirely clear to me how one harvests energy from magnetically confined fusion plasmas. Can someone give me a soundbyte on that?
You're asking for a simplification when there is no way to do it without lying. The fact is you do need to know more than a layman to appreciate how impractical ICF really is or how useless looking at Q is in nearly every context that matters. No MCF machine has even attempted to get a higher Q in the past 25 years. Look at lawson criterion and scaling laws for progress.
How much power the subsystems takes has no influence on the plasma's performance. How much power goes into the plasma (and what type of power and where and when, etc.) do influence the plasma's performance.