Yes you should always think about optimisation, even if you never end up coding for it. Every function I write I think about what is the effect that it will have on the rest of the code and what will I need to change if it later turns out to be a bottle neck. The advantage of this is I sometimes avoid writing some dumb code - even if it never matters from a performance perspective I have thought a little bit more deeply about what I want to accomplish.

To answer your question how does thinkthencode sound?

I think the operative word is "premature". If you actually have a reasonable idea of how much data you're going to be working with, it's not premature at that point to put some time into optimization.

Also, I would restate the rule as something like "don't spend too much time prematurely optimizing. If you're building a lookup, it's obviously a Good Thing to use a hash instead of a linked list, and in 99% of cases shouldn't take you any longer to code.

While not particularly original, I would place this under 'thoughtfulness' / 'thoughtfully'. Code thoughtfully, but don't dive into premature optimization.

design