Alteration: Magic Resistance: 30%
Alteration: Atronach: 30%
Block: Elemental Protection: 50%
Before even factoring in enchantments, pots, etc. seems far too easy to go immune to spells either passively or just from raising your shield.
This assumes 1) effects are additive 2) absorbing magika also means you negate the 30% as well, and 3) There isn't a cap (ie 85%)
Edit:
1) Thanks all for your input.
2) It would seem there is some debate on assumption 2 and 3
3) Another thing pointed it out is the difference between elemental damage and other spell effects (ie paralyze)


