I talked the customer out of the feature that required it, so I just moved on. I'll get back to it later.

I was going to use the EEPROM as a "dual port RAM". The customer wanted to write data to me via I2C, so my PIC would have had to be an I2C slave. Rather than go through the hassle of that, I was just going to have them write to my EEPROM (they had access to the same SCL and SDA lines), and then I would occasionally read the same location. If I got an error during read (because they were writing at the same time), I would just read again. I told the customer that they would have to verify every read that they did. Since the data changed only every few seconds, I figured that this was a great way to get the job done.

Until I found that I couldn't write to or read from my own EEPROM!

I'll let you know what I find. It will be a few days before I get back to this.