Hi Guys,
It doesn't make much sense to purchase a chronometer grade ETA caliber and then replace the escapement and balance - those are the components that make it chronometer grade. Likewise, I find it impossible to imagine that, "A lever is individually made for each movement", or at least I don't know what that could possibly mean.
IF those comments come directly from IWC, then let's take them with two grains of salt. 
_john