Are long XPath statements inherently bad?

 Sorry again, I am relatively new to XSL.  I am trying to put together 
of events as a table by outputting a list of items in each cell by 
executing queries such as the following (this is actually simplified):
select="$newshome/item[(_at_)key='recurring']/item[(_at_)template='event'][( 
@yearspecific, . ) != 1 and substring( @date, 5, 4 ) = $moday ) or ( 
@yearspecific = 1 and substring( @date, 1, 8 ) = $date )] | 
$newshome/item[(_at_)key='recurring']/item[(_at_)key=$year]/item[(_at_)template='event'][( 
@yearspecific != 1 and substring( @date, 5, 4 ) = $moday ) or ( 
@yearspecific = 1 and substring( @date, 1, 8 ) = $date )]
Is it just my syntax/logic that's bad or is there some better way I 
could/should do this?  The requirements for including events for a date 
are actually pretty complex - this is just one of a series of queries 
(which I would be happy to share!) to get events for a date.  Are long 
XPath statements always bad, other than just the possible readability issue?
The calendar does have performance issues and I will probably rewrite it 
in .NET.  Would you expect XSL extensions to be helpful here, or just 
use pure .NET (maybe an ASCX) or something I'm not thinking of?
I probably need to convert this to CSS positioning and I'm not sure if 
that would help with the problem or make it harder.
Thanks in advance,

  -John