Never saw a need for accounting between a couple. The couple is a team, pay the bills, live life. Who cares. Just always seemed like per-charge accounting and "keeping track" is an easy fiscal path to tit for tat complaints/annoyance/arguments. Might as well map how much electricity each person uses at that point, who flushes the toilet the most, etc.

Each should have private charge and checking accounts if for nothing else than gift buying. Have a joint account for most of the money, especially important if one or the other becomes ill or dies. Otherwise survivor access becomes tricky instantly.

Not poo-pooing the methods of others, the more complex methods just seem like overhead, but if they work, they work.