Why are some files allocated with BLKSIZE=32000?

Document ID : KB000094857
Last Modified Date : 07/05/2018
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In the installation JCL some files like the AABDDATV and CABDDATV libraries are allocated with a blocksize of 32,000. 
Considering the capacity of a 3390 track is 56,664 this is wasting a lot of DASD space.
Is there some restriction that prevents these files from having a more efficient block size?
The block size for the AABDDATV and CABDDATV libraries do not need to be 32,000.
All future PAX files for CA Datacom products will be changed to use half-track blocking, 27,998.
You can change the install JCL to use BLKSIZE=27998.