No it cant I am saying it wouldn't really make sense to have 2 different forms of transportation, thats like having 2 different weapon systems, or having 2 different systems of magic, I just dont see a plausible reason why they would include it
That's one of the reasons I stated it should be optional... so that you don't get 2 different forms at the same time.
Here are my reasons, as I stated not so long ago, why I think it should be included:
1. I like realism. I feel that you should walk/run or use a horse to get somewhere in the wilderness. Between cities I want a transportation system because I believe it would be realistic for cities to have some kind of transportation, especially since there is trading.
2. I like exploring. You get to discover more while you travel. And since Skyrim looks pretty nice, it makes it even more interesting
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3. You are often forced to travel, experience the environments a lot more. You also meet more people, etc.
4. When you travel to some place, it gets harder. A long journey actually feels like a long joruney. And when you arrive you feel like you've earned it.
A transportation system is also nice, because sometimes it does get a bit ... tiresome. I think a transportation system is more immersive than fast travel, because there's a more logical reason. You have to pay, find someone who can make the travel possible, etc... instead of just clicking on a location on the map and instantly get there.
The only illogical thing about a transportation system like Morrowind is that you still instantly get there once you find that person who make the travel possible and pay that person. Perhaps Bethesda can improve this a little more by actually seeing you being in a boat... traveling. And then, if you get tired of it, just press a certain button and the character would go to sleep and wake up at the final destination