The concept of doings things differently from everybody else is a double-edged sword, which has to be handled with care in case it cuts you just as badly as your foe. But it does give us something interesting to think about when we apply the idea to table tennis.

Being different from everybody else in table tennis can apply at a few different levels. You may have a particular technique that is relatively unique (such as the first players to use a banana flick, or the Seemiller grip), or perhaps a style of play that is not seen very often (such as a traditional defender or Chinese penhold short pip hitter).

Maybe you even have a set of tactics that everybody else avoids but that works for you, like serving long almost all the time and counterlooping your opponent's return.

Doing Things Differently - Pros

• When you do things differently in table tennis, if you can perform what you do at a competent level, you automatically gain an advantage over more traditional opponents who aren't familiar with your particular thing.
  For example, I generally do better playing at a National level than at a local level. Why is this? Because as a combination bat defensive player who twiddles and pick hits a lot, my style is fairly unusual at the upper levels of play over here in Australia. So I get an advantage over many of the younger players who are fantastic when playing against fellow loopers, but struggle when they are called upon to play against a defender. At home, most of the top players are very familiar with my game, so I have to work a lot harder to win against supposedly "worse" players.
  
• When you do things the same as everybody else, you have to do them better than everybody else in order to win. That means that if you have limited time to train, or less talent, you are almost always going to be beaten by somebody who is playing the same way as you but who has more time to devote to training, or a bit more ability.
  But when you do things differently, you don't have to be better than your opponent at the same techniques. Because your techniques, tactics or style are unusual, your opponent has to deal with your unfamiliar game, while 90% of your opponents will all play the same way, which makes life easier for you. So you can actually be less skilled than your opponent, but still win because he can't use his skills the way he is trained to do!
  

Doing Things Differently - Cons

• It can sometimes be hard to tell whether you are an innovator or an idiot, especially when you first come up with an unique idea to try out. Things that sound good in theory don't always work when you step out on the court and actually try them out. There is sometimes a very good reason why nobody else is doing it the way you just dreamed up - because it doesn't work!
• In order to do things differently, you have to spend a fair amount of time attempting to master a new way of doing things. Not only is this time often wasted if you decide that the experiment didn't work out, but even if you decide it was a success, can you ever be sure that you wouldn't have been better off spending the same amount of time learning to play like everybody else does? That's a tough question to answer.
• Remember that there is no copyright on great ideas and innovations in table tennis. You might get a headstart, but if you really are on the right track, many others will simply copy you and within a few years you'll be facing your own technique coming right back at you. Witness the spread of the backhand banana flick return of service over the last few years.
• Finally, the urge to innovate can get under your skin, and you end up spending most of your time trying to come up with different ways of playing the game. Instead of settling down into a playing style and mastering it, you end up switching back and forth between each new experiment that you come up with, hoping that your latest great idea is the solution to all your problems.

Conclusion

I don't really know whether it's a good idea to do things differently in table tennis or not. A successful innovator can certainly leave a mark on table tennis, such as the inventor of speed glue, the creator of combination rackets, the introducer of the banana flick, or even someone like Danny Seemiller who invented his own grip! And at an amateur level, playing a different style can certainly help you against opponents who won't be familiar with the way you play.
On the other hand, considering the relatively limited number of true innovations that have appeared in table tennis over the last 50 or so years, you would have to think that the odds are against you if you believe you have come up with an idea that will turn you into a world champion. But if you don't give it a go, you'll never know, will you?