Loyalty bloggers love a good two-player strategy, and this one from View from the Wing is a tidy example: the writer and his wife hold cards on each other's Bilt accounts so that a single household effectively gets two of everything the card caps.

The centrepiece is the Bilt Palladium Card, which carries a $495 annual fee. It earns up to 1.25X points on rent and mortgage payments with no transaction fee, 2X on everyday spend, and comes with a sign-up bonus of 50,000 Bilt Points plus Gold Status and $300 in Bilt Cash after $4,000 of everyday spending in the first 90 days. Ongoing perks include a $400 annual hotel credit through the Bilt Travel Portal (paid as two $200 statement credits), $200 of Bilt Cash a year, and a Priority Pass membership.

Here's where the authorised user angle comes in. Bilt lets Gold members spend Bilt Cash on "points accelerators" — an extra point per dollar, up to 5,000 bonus points each, five times — which pushes the card to a 3X earner. Bilt also caps transfer bonuses, typically at 100,000 points per Rent Day promotion. The catch: those limits apply per account holder. Add your spouse as an authorised user, direct her spending, points and Bilt Cash to her own account rather than yours, and she gets her own five accelerators and her own 100,000-point transfer bonus cap. Same household, double the ceilings.

Bilt has also rolled out authorised user tools that go further than most issuers. You can add kids from age 13 with parental controls, per-transaction and monthly spending limits, and merchant category restrictions. Each card gets its own number, so one lost card doesn't force a reissue for everyone. Users 18 and over can generate virtual cards for online shopping, and account holders choose whether an adult user's rewards go to them or to the user. Bilt says authorised users 18 and up will be able to build credit history on the card later this year.

The next step in the writer's plan is a mirror setup: he keeps the Palladium as his primary, his wife gets the Bilt Obsidian Card — a $95 annual fee product earning 3X on either groceries (up to $25,000 a year) or dining, your pick, locked in for the calendar year, plus 2X on travel — and each becomes an authorised user on the other's account. Two primaries, two sets of bonuses, two caps.

Why should a traveller care? If you redeem points for flights and hotels, transfer bonus caps are the silent ceiling on your haul. A household that plays this game properly can convert significantly more spending into award seats each year without opening a second full-fat card, and the granular controls make it workable for teens, sitters and partners alike. Note that Bilt is a US issuer, so this is only relevant if you have a US credit profile — and as ever, card terms change, so check current offers before applying.