Personally I think if you turn on forwarding at the account level, everything should be forwarded straight away and no filters or spam processing should be done.
If you forward a filtered set of emails (if that's even possible in gmail) then you presumably know what you're asking for.
The joke is that filtering seems to happen prior to spam classification, so you can use filtering to get around this oversight (there are example cited above).
If you forward a filtered set of emails (if that's even possible in gmail) then you presumably know what you're asking for.