Fillet Brazing - Fillet brazing consists of laying down a fillet of brass with a concentrated torch flame. This technique is excellent for producing frames with limited angles for which lugs are not available. A small electric arc fuses the tubing together, making it very strong and durable. Because not only are lugs the strongest method of joining two tubes together, they truly add individuality to a bicycle. Strip the paint off of most bicycle frames and it would be hard to tell the difference between them, but not with a beautiful lugged, bicycle frame.
Lugs show the true skill of a builder.
Truthfully, good TIG welding is not easy, but decent TIG welders are easy to come by. The only reason most frames are TIG welded today is because it is much cheaper and the clean-up time is greatly reduced. Lugs used to be an art. People would wait a long time to get a frame handcrafted from a famous builder. Sometimes bicycle makers forget that there is more to creating a bike than just making sure it works.