You'll get what is says on LH's website. The MSC rule doesn't apply when going in/out of the US - even then they don't always subscribe to the MSC rule.
Source: had to pay $150USD for a single 28kg bag when they woulda given me 2x 23kg bags for free on a recent LH JED->FRA connecting to UA FRA->EWR. As a side note I find it annoying when I like to carry one checked bag at 28kg and they charge me for that, but will let me on with 2x23 = 46kg for free...