putting a resistor in is like in your terms putting a pressure reducing valve in your main water supply and wondering why your shower doesn't work.
A fuse is basically there to protect what ever is connected to it, should something go wrong the fuse is designed to "self sacrifice" cutting off the electricity supply.
although some christmas lights do have a fuse lamp (most do now i admit) if it goes and there are no replacements available what are you going to do ? put in an ordainiry lamp? where is your protection now?
what if the cable to the lights gets trapped or say a metal tray falls edge on to the cable (not severing it but puncturing it) if you had a fuse it would self sacrifice a resistor may just get very hot (it may even explode!) which means in this case the tray you just dropped is now live, pick up tray and...............
No thanks, as an oil heating engineer would you put petrol in an oil boiler,(as fuel not in replacement of the water) its flamable isnt it? whats wrong with that it will burn get hot yeah marvelous good idea NOT!
( I AM USING PETROL AS A EXAMPLE OF WHAT NOT TO DO)
that is what you are doing by putting a resistor in place of a fuse.
You are a tradesman, would you use a toffee hammer to put in a 6 inch nail, course not, you would use the correct tool for the correct job
just out of interest fuse lamps are not as good as you may think, yes if it goes the lights will not work, but the live is still flowing all the way through the other lights, they dont work because the live stops at the fuse lamp, so if it for example at the end all the previos lights are still LIVE try it with a "volt stick" and see for your self
if the plug to fuse goes then all the lights will be dead since the fuse is in the plug before ANY of the lights
Normally i respect your posts and what you say, but resitor oilman, come on admit it you are practising for April the 1st