Retirement tax questions

"massively larger" ?  Like how much is "massive".

 

....a major slip-up in the entry in box 1 or 2a could give that result,

...like double-hitting a number key, or inserting a comma in place of a decimal, thus reporting a larger distribution than was actually done.

 

____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*