The tiers are as follows: 5% on purchases at gas stations (usually includes the convenience store as well) and 1% on all OTHER purchases for the first $1500 of purchases in your anniversary year; 3% on gas station purchases and 0.5% on all other purchases for the next $1500 of purchases; 1% on gas purchases and 0.25% on all other purchases for all purchases over the first $3000.

BTW, if you call up and ask questions about these tiers, most reps won't know what you're talking about until you specifically tell them you have reverse tiers and to look up the T&Cs. They're trained to deal with the regular Discover tiers and most reps haven't dealt with these specialty cards often or at all.

In principle, the tiers reset on your anniversary date, but in my particular case, the tier reset didn't happen until two billing cycles LATER, which kinda sucked.

The Citi card is certainly nice. I would recommend using the Discover card for your first $1500 in purchases, and if you happen to exceed that (KEEP TRACK!), then move your gas purchases to the Citi card to continue earning 5%. In my case, I buy gas at Costco so my non-Costco gas purchases are minimal - I just use the Citi card.

If you have a Costco station handy, it will often be more than 5% cheaper than your other stations (it certainly is around here)... check it out on a few different days to see if this is usually the case, and if so, you will save more by gassing at Costco than elsewhere. Keep in mind you can't use your Discover or Citi cards at Costco, of course, but you *CAN* use any AmEx, like your *Wood card or the Costco card. The Costco card earns (up to) 1.5% cashback you'll still be earning some rebate as well! Your *Wood card would earn the usual points, valued however you choose to value them.

Just thoughts to keep in mind, and numbers to crunch.