On Tue, 17 Mar 2015, Joe Delahaye wrote to Markus Reschke:

 MR> Current practice is to strip SEEN-BYs at zone and domain gates 
 MR> since their 2-D nature make them useless for duplicate message 
 MR> checking beyond a given zone.

 MR> The hpt documentation has a section about zone gating under "4 
 MR> Advanced Concepts in HPT".

 JD> I think that current practice no longer strips SEEN_BYs.  There 
 JD> are no longer any duplicate nets since I disolved the last one as 
 JD> far as I know.

that's here in fidonet but it does not apply to other FTNs where messages
may be gated to/from...

)\/(ark