To be clear, the amount of CaCl you need is *completely* dependent upon the milk. You may never have trouble with you low temperature pasteurised cow's milk, but I can tell you that *my* low temperature pasteurised cow's milk will not set a curd without it. Caldwell even talks in her book about a time when she needed to add it to her *raw* milk! It's a good idea to do a flocculation test to see what level of CaCl you are likely to need rather than experimenting with entire cheeses :-) I agree, though, that minimising the CaCl is a good idea. I also believe that minimising the amount of rennet you use is a good idea. However, that's about not adding more "just in case". You need to add the appropriate amount to hit your targets.