Hi Dennis,
You can safely skip the basic multiplication module, as long as you mastered the LR method. The Basic Multiplication Module is there more for completeness of the course, which is why I cover it after the LR method. Many students enroll in the course looking for specific techniques for specific situations. The Basic Multiplication module is tailored for these students who would otherwise find the mental math course incomplete.
That said, the same does not apply to any other lesson in the program. The Bridge, Vitruvian Man Method and UT Method for multiplication are all different ways to multiply that will work faster than the LR method for complex numbers like 3 Digit x 3 Digit multiplication or 5 Digit x 2 Digit Multiplication. You should spend time mastering those lessons and should not solely rely on LR method for this reason.
Let me know if this clarifies.
Abhishek