Guy Betsy,
Thanks for the clarification. That is what I assumed but wasn't sure.
FWIW the 3.75X means that you take the base flight miles and multiply this by 3.75 to yield the total LH M&M status/program miles accumulated in paid first class. The 25% uplift for FTL/SEN is applied against the 300% figure, not the base mileage figure. Hence 3.75X. At least that's how it's been working for me for the past three years.