At work we've recently tried to agree on a set of perltidy rules. We came up with these: 
-i=4        # 4 character indents in blocks
-pt=2       # "horizontal tightness"
-wls='=>'   # ensure there's always space to the left of =>
-wrs='=>'   # and always to the right of =>
-vtc=0      # always break before a closing token
-l=79       # 79 characters wide please
-nolc       # no "outdenting" for long comments - indent them properly
-nolq       # no "outdenting" for long quotes/strings
-sot        # stack opening tokens - same as -sop -sohb -sosb
-sct        # stack closing tokens

[download]
But they seem to result in unexpected changes like this: 
-    error(300) if $@; # 300 = GSI_BAD_ID
+    error(300) if $@;    # 300 = GSI_BAD_ID

[download]
and this: 
     my $d;
     $d->{status}      = 'queued';
     $d->{description} = 'The action was successfully queued';
-    $d->{id}          = '12345'; # Identifies action request
+    $d->{id} = '12345';    # Identifies action request

[download]

So my questions are:
1) What's the point of these changes?
2) Which options control them?

I read the docs but did not find anything relevant:
http://perltidy.sourceforge.net/perltidy.html#formatting_options
http://perltidy.sourceforge.net/stylekey.html

In reply to Why does perltidy mess up whitespace before inline comments and equals? by will_

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