There is a separate soft cap for each (combat and crafting). You probably won't need more than one account, unless decay can happen all the way back down to skill level 5.
I wish all skills would have been under the same soft cap, but... Oh well. As of now, it seems we'll all be able to be an elite crafter and elite combatant on one character, which I don't agree with.
Ive got one. might possibly get 2, one for me, and one for my son...all depends on how his report card is looking..haha
I've been thinking about how it would be nice to be able to have an alt to play with a small homestead outside of any tribe I may join's territory, just for the fun of making a solo one.. I guess it would depend on how the game goes and how I take to it
A lot depends on how stat/skill decay will be implemented. I have heard quite a few different opinions on "how it will actually work", but nobody really knows at this point, it seems.
If the decay is fast, it will mean constantly "grinding" the skills/stats that you want to keep as your main focus on a character. That could become tiresome if you have more than 1 account.
It could also mean that having an alt account that is not used constantly will lose all it's stat/skill progression after a while.
A high-skilled crafter would have to make and destroy items, not because someone needs these items, but simply to maintain his skills, for instance.
Quite some people will have more than one account, it's the nature of the beast.
Competitive players will be using all means they have to get a competitive edge, amongst these means will be multi-accounting and multi-boxing. Personally I consider it as a from of cheating but of course I'm aware that it isn't cheating in the sense of violating the ToS.
We will see how it pans out: I assume there will be a lot of homesteads in the game that are placeholders for alt accounts. I also wouldn't be surprised to see tribes forming "alt-tribes" to cover more resources.