Originally Posted by grizz1

It's not a matter of the engine having a "weak" rod. Any rod placed under that much strain with millimetres of very, very tight pinch to push through for the first couple of gallons of it's life won't like it - particularly the first 10 tanks or so.

The rods are designed to take the stresses of the high revolutions when moving in a nicely fitting sleeve without issues, but the stresses and strains on rods, and particularly wrist pins and wrist pin mounting recesses in the cast pistons on a new motor this tight are extreme.
It's not uncommon on engines this tight that have been run in mounted in the car with less than precise temperature control over the early tanks to have significant wrist pin slop after a gallon. We have seen this time and time again with super tight new engines.

You can easily change the rod after run-in (highly recommended in the large majority of the tight fitting Taiwanese produced engines), but you can't repair the worn out wrist pin mounting areas in the piston.
A nice firm fit for engine longevity is one thing, but crazy tight tolerances that cause significant internal wear and tear before the engine is a couple of gallons old is something else.
Like Rex stated - they are just too tight now days.