A lot of times, writing something out in BASIC can help you set up a general structure for your program or test a routine or formula or something that would be a lot more complicated in asm. I guess that's different than writing half a game and switching over to asm, but i think if you have a decent knowledge of asm it's not really a bad idea. I've seen what you're talking about happen a lot too, but i think that is, like you said, people who were really efficient in BASIC but had no knowledge in asm.