Q&yourA: Keeping a baby asleep when you put them down

And now for a classic. I sure can't solve it, but I know we've all got tips, and maybe one of them will work for Andrew, who writes:

"How do you keep a child sleeping when you put them down out of your arms? My 4-month-old daughter has this propensity to sleep heavily when we hold her but wakes up as soon as she is put in the crib, cradle or pack and play. Please help."

Yes, and yes. I remember it well, both times. Out like a log, or at least a lumberjack, in my arms, and then two seconds after being put down, AWAKE. And not happy about being awake.

The only success I ever achieved was lying on the bed with the child next to me and nursing/snuggling to sleep, then waiting until the baby was completely out (10-15 minutes after falling asleep) and then rolling away slo-o-o-owly. Of course, this is a physical impossibility if you're trying to get the baby to sleep in a crib.

Anyone have any help for cribs?

The other path, oif you're not wedded to crib-only sleep, is to wheel the baby in the stroller until she falls asleep and then just leave her there for the nap. Or in a swing.

Just know that almost everyone struggles with this, and it will pass, and I don't think there's an actual magic bullet.

Suggestions? Memories? Laments?