Agreed.  And since very long URIs can occur anywhere, we should  
avoid a <FIG>-specific solution.  The best practical solution is  
probably to make use of element content inside <HEAD>, which is by  
default not rendered.  In other words, what we need is a non-empty  
form of <LINK>, and support for indirect reference to <LINK> URIs.
For the first, perhaps </LINK> could be made omissible, instead of  
having <LINK> be empty?  That would simplify matters.  If not,  
invent a new tag like <LLINK>.
For the second, we could either create a new common linking  
attribute (extending the current list of REL, REV, etc.), or allow  
LINK indirection as I have previously proposed.  Link indirection  
means: if the target of a link is a another link, follow it too.
So, if </LINK> can be made omissible and link indirection seems  
like a good idea, we could use the following mechanism for very long  
URIs:
 <HEAD> <LINK ID=xxx>http://www/script.class#x=1;y=2</LINK> </HEAD>
 <BODY> <FIG SRC="#xxx">...</FIG> </BODY>
The use of element content for URIs does present additional  
encoding complications, as you say, but placing URIs outside of the  
document would be even worse from a practical point of view.
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Paul Burchard	<burchard@math.utah.edu>
``I'm still learning how to count backwards from infinity...''
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