If you think that this knowledge will be important to your employer then try not to share it too much in an organised and documented way but rather help others on specific issues. This is more effective to establish yourself as the expert and go to person. If you write a comprehensive documentation they others need you less.
Yikes. Would you want to work in an environment where all your coworkers acted like this? Your suggestion may be necessary in a cut-throat workplace, but I'd be more inclined to GTFO and work somewhere that my team members actually try to help each other, instead of always acting in their own self interest.
Of course you should be helpful, but you should also be smart. You want to be seen as valuable AND as difficult to replace. Help your employer succeed and help yourself succeed at the same time.
What would you rather hear in management meetings?
"We can't let Bob go, he's the expert on X, everyone goes to him for help and we need him" or "Sure Bob is an expert on X, but he wrote down all he knew so we'll manage".
See, it's not about not helping, it's about helping while building and retaining leverage.
That's why companies want to encourage "knowledge sharing". It's not to foster a friendly atmosphere, it's to be robust against someone leaving and to prevent someone from having too much leverage. Most experienced engineers know that and tend to be wary when asked to document what they know in details and/or to train others.
As to act in one's own self interest, well sorry to be the one to break it to you, but that's how the world works in general and that is especially how the workplace works. And in fact that's how everyone works when there's a choice to be made. The sooner you realise that the better off you will be.
Well yeah I guess this is what some people actually do. Personally I would never want to work this way though. And besides, there is probably no-one that would document all they know any way. Simply because no-one has time to write everything down and no-one has the time to read all that text. But aiming for good documentation is still a good thing IMO.
