Sorry to say eric, this is not a result of less competent tech's installing these block heaters, based on the number of recent fails in states all across the country. Maybe read the entire thread(s) before jumping in with fake misleading news, that helps no one.
From the most recent instance in Montana, the OP tells us what the field service tech told him:
"RE:RX7320 problems @7 hrs on the meter
The mechanic showed up and put the block heater back in. It had red locktite applied to the threaded adapter which was then tapped into the frost plug hole with a hammer and socket. He said that this did not used to be a problem but there have been several of these coming out lately. His thought was that the insert that was tapped into the freeze plug hole was being manufactured differently in the last 6 months and does not have as tight of a press fit as it should."
The block heaters blowing out of the block has happened on RX and (POSSIBLY some NX series, though I can't currently find a link to a thread about that model also having failures, at this moment). At least one case of valve train failure and engine destroyed, low hours, but off warranty. Another is currently waiting on an oil analysis to determine the damage at 7 hours on clock, brand new tractor, (cited above). These are not likely improper installs, though final determination is still out at this point.