Thank you all, this is so much food for thought. These aspects of the game are so interesting. Am only now building up alternate rune sets for easy trial and error. Klepto's practical Rune guide is also my new game bible.
I look forward to Herby's results on the Shayd blocking test. Reading above, I realize I will have to play with infallibility myself for shayd and blood. Any tips on how to test would be appreciated... I am going now on feelings and twinges.