Do you sand your wooden worktops by hand or do you use a sander?

[shoom]

The oak worktops look okay, but have pale patches where they obviously need re-oiled. I've bought the house from people who haven't maintained anything in the house so I've no idea how they've been treated from installation. It looks like they've been oiled then ignored. I don't see any black marks or other damage. Should I just scuff up the finish, clean the dust off then re-oil, or is it worth sanding properly and restarting the process?

I sand by hand. You get a very smooth finish and don't actually need to sand that much so hand seemed as quick as using a sander.

Thanks.