Paul Lavings

One of the common laments you hear at the bridge table is “Partner, I couldn’t bid 4♦, cause I might push them into game”. This is very negative thinking, as it could equally be phrased, “Partner I had to bid 4♦, to try to push them into 4♥”.
Firstly, if opponents think they can make 4♥, they would have bid it by now. Secondly, it is important in partscores not to sell out at too low a level. And thirdly, yes, opponents might occasionally take the push and make a game, but you will win in the long run.
One fear of pushing the opponents into game is the indignity of it all. You may be the subject of considerable gloating and guffaws, and some find this unbearable. My advice is to get over it. Work it out, and learn to live with it knowing you did the right thing. It’s like losing a finesse to the singleton king: so what!
This deal came up a week ago, in a Saturday afternoon game:

 Perhaps not a good example, since it would be extreme cowardice not to bid 4♦, but all the elements are there. No one really knows who makes what, and East has the sort of hand where 4♠ could easily make. In fact there are only three losers in 4♠ but East runs out of trumps, and 4♠ fails. When you dare them to bid 4♠, they invariably
decline, and 4♦ is an easy make.

This deal is from the recent Olympiad in Lille:

The double of 1♥ denied spades, and showed clubs with less than a two-over-one 2♣ bid. It looked like opponents could well make 3♥, and we probably had a 5-4 club fit.  Maybe opponents make 4♥, no one knows, but they probably won’t bid 4♥ over 4♣. We picked up one imp for +130, but it let opponents know we didn’t come all this way to pass.  
The message is to keep pushing. Push them from the two level to the three level, and if your instincts tell you, from the three level to the four level. And please, please, push them into game.