In a bank if you deposit X coins you can withdraw at most X.
My bank must be weird, they let me withdraw more than X and let me carry a negative balance for a little while (a service they charge for).With the accounts feature, if you have an account containing X bitcoins there are two ways to overdraw it:
1. Using the move command. Negative balances have a lot of use-cases, and last time I checked accountants know how to deal with negative account balances.
2. Using the sendfrom command, if a transaction fee is required then the fee is charged to the "sendfrom" account and may take it negative.
Are you sometimes using "sendtoaddress" and sometimes "sendfrom" ? Or are you using both the GUI (designed for a single user's wallet) and the RPC? If you want to use the accounts feature, don't do that, always use "sendfrom".
Better accounting for transaction fees is a valid complaint, always deducting the fee from the "sendfrom" account can be annoying. It doesn't violate accounting principles, though; if you want the transaction fee to be paid from some other account, then you just sendfrom() and then move() to adjust account balances.
If you really want to find something about the accounts feature to complain about, then you should complain that it doesn't scale.
