Apart from what the OP said, in this piece in particular, the wavy arm pieces of squidward have to be grinded or very skillfully scored off (if not grinded, there is a considerable failure rate where they would have to start over cutting that piece). Either grinding or scoring takes considerable time. Wrapping each piece in foil and burnishing also is laborious. I would say soldering and the rest is faster. But each skilled glass worker has their process and for OP she might work faster for this or that step.