A few things.
Yes, Fusion Subs have the ability to be Fusions Subs while in the Deck. They have that ability while in the Hand, Graveyard, Field and RFP Zone already. Why not the Deck?
The reason you can't use Fusion Subs with "Future Fusion" is simply a Because Konami Said So ruling. It is currently the ONLY Fusion Summon method that cannot use Fusion Subs.
So, having said that, to answer the initial
[url="http://www.cogonline.net/threads.18682&highlight=future+fusion#"]Question[/url]. Yes, you most certainly CAN use Fusion Subs with "Vehicroid Connection Zone". However, as DaGuy kindly pointed out, the only monster you can currently Fusion Summon with "Vehicroid Connection Zone" prevents the use of Fusion Subs.
Just because the monster prevents Fusion Subs, doesn't mean the card can't use them.
Hope this helps!
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Simon Key
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