[ozwarrior]

Hi Kodiak. Looking at this service sheet it would suggest not in relation to the DCC socket but it may pay to check with Hornby to be on the safe side.
http://static.hornby.com/files/ss-251c-226.pdf
It does however have the 5-pole can motor in the loco.

 

[ozwarrior]

Regarding you question about 5-pole motors this article on z-scale asks some good questions:
"Do you need a 5-pole motor?" & "How to tell which motor you have?"

http://www.zscale.org/articles/fivepole.html#tell

With regard to steam locos most new Hornby are 5-pole whereas most Bachmann I believe are 3. That said no one seems to be complaining about the 3-poles so other factors must come into play.