Resistors in the ignition leads

Do the ignition leads need resistors?
Went out for a drive, all good after winter, oil, temp & water ok, fresh tanks of petrol. After about 45 minutes started stalling off the gas & when stationary. Made it home by avoiding traffic lights & blipping the throttle. At one point I’d called breakdown, but managed to start & keep running. Seemed fine when running.
Anyway
Next day, dead & I made things better by flooding the engine…
Local mechanic came out. Identified that spark was weak at the plugs & good at the coil. New plugs & dry engine & running ok again.
He pointed out that I have resistors on all over the distributor, where the king lead connects and all 8 leads. I’d leant him my Steve Heath & he pointed out that neither the 4.3 nor the 500 have resistors in the photos of their distributors.
What’s going on? I still have extenders which I’m told are ok.
The leads are standard aftermarket. Plugs are NGK B7ECS. The ignition has been problematic over the years, I’ve lost the ignition module & coil in the past 5k miles.
This is the resistor which used to be on the king lead. And a ruined plug.

Some carbon based plug leads are self suppressing due to the inbuilt resistance.

If you are using solid copper leads, then you should be using plug caps with built in resistors.

But there should only be one set of resistors.

As per the post above - the resistors are used for suppression (reducing interference) from the spark plugs (the spark in reality).

From memory, some spark plugs also have built in resistors, IIRC the NGK models typically used to reference this with an 'R' in the model number.

Finally, the king lead shouldn't need a suppressor.

To test your suppression, get a Medium Wave radio nearby and if it has a clicking noise that speeds up when the car is revved, your suppression is not working properly.