Бомбы на центральном узле подвески бывали, конечно
Например 1 февраля 1942, Квадж - вот отсюда http://cv6.org/ship/logs/action19420201.htm#raids пункт 2а: Nine TBD's, which were somewhat later in reaching the objective, also attacked Kwajalein. The SBD's each dropped one 500 lb. bomb and two 100 lb. bombs. The TBD's dropped three 500 pounders.