I used the blocks and bragged about my calc levels for about 6 months, until my calcium kept going up and up. My last reading prior to stopping was at 650 or who knows because my kit is only accurate to 500. I always thought I had a bunk test kit!
Anyway the blocks work great for initial start, but for the long haul I am starting to use seachem products and sort of following the "garf" recipie.
I will be holding on to my blocks for if and when I deploy and will tell the wife to just throw 1 in eveytime the last one disolves making it extremely easy on her.
My lfs mainly uses the big 1k blocks and a calcium reactor and thats it. Oh ya, you need to suppliment iodine as the blocks don't have enough for a reef system.
Your right the dosing is confusing and I guess that I'll be joining you in that learning curve.
Best of luck!
Paul