Holding miles for 6 months is not "hoarding." But whatever it is, it's an undesirable aspect of Alitalia's MilleMiglia program.

Moving back to Aeroméxico's program, anybody have any opinions on it? Elite tier thresholds look typical (50,000 miles in any 12 month period for SkyTeam Elite Plus), both elite and reward mileage earning looks generally better than Delta now, there's a 500 mile minimum earning per segment (and usually 625 miles minimum), and there are some decent partner tie-ins (like a U.S.-issued Visa credit card). Reward mileage levels look generally pretty good, and some of them are rather attractive. You must credit at least one flight every 24 months to keep the miles active, but the miles never expire if you do.

Looks pretty good to me.