You're quite right.. It seems Australian tablespoons are 4 teaspoons, or 20g!
I've made this base a few times, and it is good, but I wouldn't suggest anyone here has a go in a hurry. You already have some great base recipes on the site, which seem to be getting good results. I guess this was more of a "see how we do it over here" kinda thing. It's also worth noting that there are quite a few other differences between English and Australian Indian restaurants. For instance Chicken Tikka over here, is a totally different marinade to Tandoori. It has a yellowish color and a different taste, whereas Tandoori here (like in the UK) is bright red. Also our Vindaloo is quite different to yours. Over here Vindaloo is alot more tangy, and seems to have more vinegar, and possibly tamirind or something in it. I'm sorry I can't explain it better!