duplicate entries in preseed.cfg?

[Jim Avera]

I'm trying to learn about automated installation.  In the provided 
"example" preseed.cfg at

   https://www.debian.org/releases/stable/example-preseed.txt
entries for partman/{choose_partition,confirm,confirm_nooverwrite} 
appear twice, once after stuff related to EFI and again after stuff 
related to raid.

Is it useful/needed to repeat certain items at different stages? Could 
the same item be specified differently in different spots meaningfully?