Personally I think the SEA curries are a bit more forgiving than the Indian ones. Indian curries use a lot of dried ingredients, where as in SEA they tend to use pastes made from fresh spices (in Indonesia and Malaysia this is called bumbu) as the basis for a lot of their cooking. Which gives you a little more room for error when it comes to quantities for most things. You just grind everything together with your onions (or usually shallots), fry it off a bit, and get on with the rest of the recipe. If you add a little too much fresh galangal, it’s not much of a problem, but it’s a lot easier to throw the balance of a dish off with dried powders.