Dear Ed & Peter,

I have read that sometimes it can be wrong to overruff, but when I am at the table, I find it hard to recognise these situations and am afraid of being reproached for discarding instead of ruffing.
Could you clarify the right situations in which not to ruff or overruff?

Thanks very much, I enjoy the site
Alan

Answer Ed Hoogenkamp (South)

Dear Alan,

It's usually wrong to overruff if you have a certain trump trick of this kind: QJx, J10xx. You shorten your length in trumps and because of that declarer can pick up your trumps easily later. Especially if you have J10xx: this is usually a disappointment for declarer ('darn... trumps 4-1') and keeping your four-card suit intact will normally give declarer a headache at least.

That brings me to the second situation, which is similar: with trump length but no certain trump trick it often pays not to overruff from holdings like 109xx, 10xxx, 98xx.

A third argument: if you don't have a good card to play back after having overruffed, you maybe shouldn't have done so...

Read more about the subject in a Bols tip we published from Jean Besse:
Beware of your trump tricks. When you see a chance for an early overruff, don't be in too much of a hurry to take it. 

Of course I can say much more about the subject, but that would be very unfriendly towards my good friend Peter; he is home, watching the snow fall... imagine there is nothing left for him to add? That would not be nice, so Peter: the floor is yours! 

Un saludo, greetings from Barcelona

Answer Peter van der Linden (North)

Dear Alan,

Once more Ed is wrong since (a) there is no snow here (actually, until 20 August we've had almost four weeks of non-stop warm — 20 degrees centigrade plus — sunny weather) and (b) I am not so arrogant as to think that I can improve on (or even just add to) Jean Besse's excellent Bols Tip article.

OK, one tip: analyse every time you have overruffed or have refrained from doing so. Or even better: analyse every time you have been overruffed as a declarer. Would it have been better not to overruff?
You will find that the most important argument for not overruffing is that it may cause declarer to lose trump control. So not overruffing applies especially if declarer's trump suit is relatively short.
But don't exaggerate: if I can take an overruff from an original holding of something like 9x or 8x, I take it, automatically...
(On the other hand: if I defend and Ed is declarer I never overruff. After all, confusing Ed is bound to give me at least two extra tricks.) 

En hils, regards from Orkanger