patcanuck, on 2022-October-11, 19:06, said:
I've read discussions about the strengths and weaknesses of leading thirds and fifths but what I really need is to find is a good site where they go through a number of hands and explain the use of 3s/5s. My confusion is what they do with a four card suit, and how you avoid confusion when you have something like 982 where leading the 2 seems to suggest a five card suit?
Does my head in at the moment and hate the confusion. I am fairly comfortable with UDCA, standard carding, odds/evens but struggling with leading thirds and fifths.
Don't know any websites; there are some books on defensive play & signalling that discuss this (e.g. Root how to defend a bridge hand, Marshall Miles Defensive signals).
In any case, the idea is usually "3rd from even, low from odd". I've never really figured out the exact difference between this and "3rd & 5th". Perhaps it means leading 5th from SEVEN cards exactly, so that a lowest lead from a known 7 card suit (you preempted) is some sort of suit preference play.
So from a 4 cd broken suit (not holding an honor sequence where you would lead an honor), you would lead the 3rd highest card.
From 982, you lead the deuce. Partner will assume an odd number, so 1/3/5 cards; on a few hands they may not know for sure, but usually between seeing dummy, their own hand, the bidding, and how trick 1 plays out, more often than not you can figure it out.