This is quite a theory. I don't believe it, though. Here are couple points why I believe it to be false:
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/hard-talk/22605-banda-bahadur-guru-gobind-singh.html
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=22605

1) Dhan Dhan Maharaj Shri Guru Gobind Singh Sahib Ji would never have sought revenge. His rules of dharam yudh (religious war) clearly state that the this warfare should defensive and never aggressive.
2) Satguru would have never sought to decieve his followers. How could the teacher of Truth be found to be a deceiver? Where does that leave his followers?

WJKK
WJKF

Jaspreet