Meanwhile, heat oil and butter together in a large skillet. Add shallots and 3/4 cup roasted garlic cloves saute 3 minutes, until shallots are soft. Add beer and bring to a simmer. Add clams, cover and simmer until shells open, about 5 minutes. Using tongs, remove 12 clams and reserve for another meal. Drain capellini, reserving 1/2 cup pasta cooking water and add to clams in skillet, adding the reserved 1/2 cup pasta if necessary to "loosen" the sauce. Simmer 1 minute to heat through. Remove from heat and top with parsley and Parmesan. Serve with a mixed green salad and bottled dressing, if desired.