(re)raising with second best hand to narrow field

[cianosheehan]

In TOP, Sklansky talks about raising or re-raising when you are sure you have the 2nd best hand, in order to force other opponents out and increase your chance of winning.

I am a bit confused about this concept. Isnt it better to keep others in, as this will increase your pot odds for your draw? If you are certain that hitting your outs will give you the best hand, why try and force others out when they could be paying you off?

Or is this down to having a made hand, say, on the flop, and at the same time being sure one other opponent has a better hand than you, and you are trying to force out others with weaker draws to stronger hands?

Finally, do you think its profitable to incorporate these moves into your low stakes game? Particularly the $25/$50/$100 rings?

Thanks
-Cian