i did this recpie and i think it was to swaet and to thick for my taste, i dont know if its normal but i made two portions so i doubled up everything i thinks its normal and what i can say:
When you double the quantity of a curry recipe you
don't double everything in it. The spices and other ingredients are
only increased by 50% with the exception of the main ingredients like the meat / vegetables. So your spices and sugar should not be full double quantity.
eg. If your recipe called for 1 tsp of sugar then in a double recipe you would start out by using 1.5 tsp , not 2 tsp.
You vary the amount of base gravy or sauce liquid you use to your own preference anyway.
This is a general rule of thumb for this type of cooking, which is different to say baking bread or making cakes and biscuits where everything is increased by the same amount.