According to this video when you take a Seed A (e.g. HIJK99) and increment the first tryte by one to obtain another Seed B (i.e. IIJK99), Seed B is associated to the transactions to Seed A.
Every new address is generated by incrementing a seed and doing some hashing. This gives a useful feature: If you don't want to see the whole history of the transfers then increment the seed before entering it into wallet software and transactions associated with the very first address won't be shown (this process can be repeated).
The feature may work improperly if your seed has several inputs, so make sure that your balance doesn't become lower this way.