The lack of co op.
I mean mostly it can be done. but they don' t want to because it is too much work
Even in games where it just seems like it won' t work it can
just don' t make it a requirement.
That' s what Halo brought in recent times.
Look how these games did it:
Sonic 2- Adventure
Devil May Cry 3
Onimusha: Dawn of Dreamcast
Can' t think of anymore right now
Lord of the Ring Third Age
Even Metroid prime could have done it (though harder to Work out)
But with the added power of the Rev they can if they try
wait they could just have done in room by room
GTA: SA the whole reason my brother bought it is co op (and exploration)
Rpgs with dual controller support is simple enough
yes also Shenmue could have but it wouldn' t have made sense but it doesn' t
have to. it is not a Requirement in the game
It was done in Legend of Oasis and it work very well even tough it didn' t make sense
Oh and in regards to Shenmue you probaly were expecting GTA 3 up freedom weren' t you? I think alot of people were. Shenmue is story driven and the search is the main part of both story and gameplay...