According to a recent paper in the Journal of Neuroscience, researchers found that...
"when a person watches someone else perform a task with the intention of later replicating the observed performance, motor areas of the brain are activated in a fashion similar to that which accompanies actual movement."This means you can actually CHANGE YOUR BRAIN by watching other people play euchre. So, if you want to become a better euchre player, put those good ol' euchre playing cards down and go watch some people play euchre.
But the important part is that you can't just watch the games passively. You've got to watch the live or online euchre games with the intention of copying the plays that good players are making. Passive observation is almost worthless for euchre game improvement.
Watch with intention.
If you can't find a live game with a great player worth watching, go check out the many online games that allow spectators. You can find them on Yahoo, Hardwood Euchre, or Pogo.