Remember, that is add a 0, as in make it 40 instead of 4, not make it 0.
Kwok, in unmodded SE4, 300k intel per turn in CI III can easily keep 4 empires with roughly the same (or even a lot more) production at bay. And that is not hard to acquire in large games (where this is even an issue). If intel projects cost 4x as much (which is more than the original proposal anyways), then 300k easily keeps out one of those empires. If you need to, you can more than likely easily double or triple your intel production (well not easily, but you can scrap those 100s of research centers you are bound to have with such a large empire). This of course assumes that you have no allies and that there are a lot of people against you.