Complex sentence: Bertrand ignored friends and advisors feeling he had two advantages in launching Mega Bloks: he aimed to produce jumbo-sized bricks for the toddlers, which Lego bricks were not designed for, and he felt his expertise in injection molding would give him a price advantage.
Split into simpler sentences: Bertrand ignored friends and advisors as he figured he had two advantages in launching Mega Bloks. He aimed for jumbo sized bricks for the toddlers, which Lego bricks were not designed for, and he felt his expertise in injection molding would give him a price advantage.