Wouldn't a dodgy ignition switch still be dodgy even when the bike was cold though?
Yes, that's another thing that puzzles me. But then I am an electronics ignoramus.
Am I feeding the electrical fairies with the right food? If I've offended them (and god knows I can offend anyone) how do I make it up to them? And where exactly on my bike do they live?
GC
Here you go GC, all you need to know

Volt - (From the German) a motorcycle will typically have a 12 volt circuit, meaning, in English, that there are at least 12 'faults' or things wrong with it. An alternative etymology accepted by some scholars suggests that the spelling should be “vault” because volts are what make you jump when you touch a live wire.
Amp – As any electrician will tell you electrical problems are caused by mischievous spirits called “Amps”, similar to Imps, but smaller.
Ohm's Law – Simply states that the further you are from Ohm, the more likely it is that a bulb or fuse will blow.
Resistance - A circuit or component may have a high resistance or a low resistance. This is a measure of how difficult it is to fix. Sometimes a seemingly minor electrical problem will resist detection or repair for hours, days or even weeks.
Electrolyte – Early motorcycles had gas lanterns. Later models had primitive battery powered lights originally called Electrolytes.
Rectifier – From the same etymological term as ‘Rector’ this signifies a person of authority and great spiritual or religious power who eventually succeeds in ‘rectifying’ the fault.
Contact – Your friend’s friend who knows a Rectifier.
Charge – A professional Rectifier will always levy a substantial charge.
Relay – Often found on older bikes. A fault is detected and temporarily cured. The bike is then sold. The new owner discovers the fault, carries out temporary repairs and hands the bike on to a new owner who repeats the process. This is known as an ‘Electrical Relay’. If the bike goes all the way round the club and returns to one of the previous owners, this is known as an ‘Electrical circuit’.
Armature - From the Italian. Someone who sits in an armchair and dispenses wisdom, but has never been seen to do any work is called, in the Italian, an Armchair Electriciano’.
Finally, Terminal - A motorcycle that has resisted all attempts of the Rectifier to cure Volt, and which has been through the Electrical Relay and completed the Electrical Circuit is defined as 'Terminal' and broken down to it’s component parts and sold for spares.
WARNING! Unless the electrical components are correctly exorcised there is a very real danger that the Amps will possess any bike to which they are fitted. Under forthcoming EC regulations, when a bike is finally dismantled it will be necessary to remove and destroy all of the battery and wiring loom, much as the brain and spinal tissue must be removed from cows to prevent the spread of BSE.