Plugs, wires, and coil

The Chrys elec ign is only a marginal improvement over points in terms of ign energy. That is why the plug gap is 0.035", not 0.060". The additional energy comes from the cleaner ' switching' of the transistor [ versus points ] generates a little more back EMF.
One of the benefits of Plat/Irid plugs is that they require less voltage to fire them. So a fouled 'standard' plug may not fire because it is fouled...but a Plat plug will fire...& will keep doing it for longer. Ignorant people do not understand this.
Pretty sure all plugs today are 'copper'. Thanks to NGK. The copper is not exposed to heat, it is enclosed inside a nickel/steel jacket. Because of it's excellent heat conduction, copper plugs work over a greater temp range before fouling.