By playing P* she's getting a return of .62.

采用P*时她能获得收益62
So one thing she could deviate to, is playing L all the time.

她可能改成一直采用策略L
If she deviates to playing L all the time,

如果她改成一直采用策略L了
her payoff is still .62 so she's not strictly better off.

她的收益还是62 即不存在严格增益
That's not a strictly profitable deviation.

这并不是一个严格有利改变
Another thing she could deviate to, is she could deviate to playing R.

另外她可以改成一直选策略R
If she deviates to playing R, her payoff will be .62.

如果她一直选R则收益仍为62
Once again, she's not strictly better off:

她同样没有严格地获得增益
she's the same as she was before,

她的收益和原来一样
so that's not a strictly profitable deviation.

这也不是一个严格有利改变
So what have I shown so far?

至此我们要说明什么问题呢
I've shown that P* is as good as playing L, and P* is as good as playing R.

我证明了选P*与选L和R是一样好的