Here's what seems to be wrong:
The sorcerer's suit has six pieces to it. Each piece has +7 in each resist, which would normally give only +42 in each resist. The difference between 70 and 42 is 28, i.e., you get a 28 point bonus to each resist when you wear all parts of the suit.
What seems to have happened is that the "sign" on the the 28 point bonus that should go to the physical resist when the entire suit is present has been changed from a positive to a negative. It looks like the 28 point bonus in the physical resist is added in when you have the whole suit on, but then it is taken away. Unfortunately, the taking away of the 28 points in physical resist seems to "stick" to your character, even if you completely remove the suit, log out, and close the client. I imagine something similar might be happening with other suits that provide a bonus to resists when you wear a suit that gives the message, "The magic of your armor combines to assist you!" when all parts of the suit are worn at once.