The -mt parameter should start at 0 for rar versions between 3.6b1 and 4.11.

[Da Fox]

When the -mt parameter was introduced in 3.6b1 the range was 0--16. In 4.20, this was changed to 1--32. See increase_thread_count() in main.py. However, it seems that it really does make a difference what algorithm is used between -mt 0 and -mt 1. Both are single-threaded, but do make different compression choices.

The following release requires -mt 0 for correct reconstruction: https://www.srrdb.com/release/details/Need_for_Speed_Carbon_Collectors_Edition-Razor1911

Full command line: 2006-08-05_rar360.exe a -m3 -mdA -s- -ds -mt0 -vn -o+ -idcd -v50000000b -mcA- output.001 rzr-nfsc.iso

Currently mt_min is set to 1 in increase_thread_count(), but it should depend on the version of RAR in use, similarly to rarbin.max_thread_count().