Quite a lot of cables seem to be made with this sort of lump of grunge on the ends - including several I've had for japanese bikes over the years. I guess the grunge is designed not to drop off the ends if some of those bywords for reliability use them, but I'm with DuTch - I like the simple tit on the end and a separate barrel on clutches, so the thing isn't going through constant unnatural acts in operation. I have never had a clutch cable fail if made that way. But throttles are a bit harder for lack of space in the twistgrip (I've found anyway).
And the 'old ways' are the best as a10gf says - not too much heat - that'll kill them as burnt strands are brittle - and a decent flux to get things squeaky clean. I make most of mine using bits of brass rod cut to size, countersunk on the side that matters, with the cable end tinned and well splayed and dunked in a 'soldering pot' as often as not. It's becoming a forgotten skill, but is actually easy after the first couple of tries. Very satisfying too. Quite useful cable-making kits can be had from a number of sources - and if things go wrong, at least we know who to blame!