Awfully good at it.
A few stat facts about him.
• He missed 3 full seasons due to WW2. In the 2 seasons prior & 2 seasons after he returned, he hit 73 & 70 homeruns. It is not unreasonable to predict 105 Homer's over those three years. The he missed all but 19 games in 2 years for Korea. Same time periods, he hit 58 & 57, so 28 per year. Add that 56, and we could project him at over 680 home runs.
• His walk to strike out ratio was phenomenal. Over 2000 walks, only 709 Ks. Nearly 3 to 1! For a power hitter. What an eye he must have had. Over his career, the % of walks per plate appearance was MORE THAN 2x the MLB average. And, his strikeout % was 3/4ths of the league average, which includes contact hitters. Unreal.
• Doing the same thing with hits, it's pretty easy to project more than 800 hits. He'd have nearly 3,500 hits.
• His on-base percentage is the highest in MLB history. .482. This is essentially reaching base 29 times every 60 at-bats.
As you can tell, I'm quite the Ted Williams admirer.