[EricK]

The LOTT says that on most hands, the combined number of tricks that can be taken by each hand if played in their longest fit is "generally" equal to the combined number of trumps.

Sometimes, though, you don't want to play in your longest fit - eg opponents bid up to 4♥ and your side have 8 ♠ and 9 ♣ and you'd rather try your luck at the four level than at the five.

What, if any, are the guidelines here?

[TimG]

I don't know the answer to your question, but I do know that when both sides have a double fit (two 8+ card fits) an adjustment to LOTT is in order. I think the suggestion is to add a trick when both sides have two 8-9 card fits.

[jtfanclub]

No expert here, but....

It's the total of your longest fit and their longest fit. In spite of the simplifications, it does NOT mean the longest fit needs to be trumps.

For example, if your side has 8 spades 4-4 and 9 hearts 7-2, you're probably going to score more tricks in spades than in hearts. But the law still uses the 9 as the base (and adds one for the double fit).

[barmar]

Here's what Verne's Bridge World Article says:

Quote

the number of total tricks in a hand is approximately equal to the total number of trumps held by both sides, each in its respective suit

Notice that he specifically refers to the number of trumps, not the longest fit.

Having a long side suit is likely to give you additional tricks. The LOTT is an average, and I expect that the cases where both sides have a long side suit are balanced out by the cases where you're all square and make fewer tricks than the LOTT indicates.

And when applying the LOTT in competitive decisions, I think the assumption is made that both sides are bidding their longest suits.