I played poker semi professionally while at University and most of my investment stake is from that period. As Alwaysinvert wrote I think the analogy is somewhat overused but a few concepts I like to think are similar are,
- Second and third level thinking, and when it its useful
In poker against very weak players you only play your cards, with weak players second level thinking is important, with good players third level thinking is important and with really good players it is all game theory.
Investing it somewhat similar. For markets with little competition valuation is everything, with strong competition second level thinking gets more important and with really strong competition it is probably not much that can be done to get an edge other than to accept that you can't get an edge.
- Using you opponents psychological pain as an opportunity
Especially in tournament poker situations arise when weaker players get scared and do not want to take risks after putting in a long time at the tables. A good player takes advantage of this bluffing into situations and forcing players to commit or fold. Similar things happens in cash games were situations were a player might look like an idiot for calling are nice bluffing opportunities.
The investing version of this is buying things that are to painful to hold or that institutions will look like idiots for having.
- and the most important one, shun competition
It is much more profitable to be an average player playing bad players that to be a good player playing average ones. This is similar to what Buffet says about when a good management team meets a bad business the reputation of the business stays intact.