For the record, a good cleric can bless items at least a decent ways past HCP. 14 CER is the highest I tried, and from a capped cleric it swung till I was bored of counting. I really should put some more time into that with all the random weighted stuff in my lockers. Anyway, the big thing I learned was that the WPS decreases bless by a static number of swings, regardless of bless. So max Voln is 152 swings, at HCP it lasts for only like one swing and if you get a cleric bless on HCP it would be <cleric bless math> minus 150ish, which leaves the upper threshold a bit open, though certainly there is obviously a scaling that happens.
"Hi, my name is Ososis and I'm blaming my shitty life for being such a fragile, soy drinking, emotionally unstable loser. My triggers are: Red reputation, ANY mention of MacGuyver and being called a fragile, soy drinking, emotionally unstable loser."