The passage most strongly suggests that:
2. Dentistry required minimal care and precision.
This interpretation is supported by McTeague's physical description and approach to his work. His reliance on brute strength and the fact that he often dispensed with forceps to extract teeth using just his thumb and finger imply a lack of reliance on refined techniques or precision tools typically expected in modern dentistry. The description of his strong, almost clumsy nature aligns with a dental practice that may not prioritize the delicate care and precision that is more common in contemporary dental procedures.