it's more of a cash game strategy these days, limp-raising AK/JJ+ to more effectively isolate heads-up on tables that otherwise see an early position raise called in 5 spots, resulting in a second best hand far too often.
a similar dynamic may exist with tournaments, in which case a balanced early position limping range isn't the worst thing in the world. but limping anything pre-flop in a tournament is generally considered pretty awful these days and limp/raising AA (and AK for balance) UTG is something we did back in 2006.
if an opponent does it now, it may be strength. depends on the opponent.