NORTH
 A54
 5
 KQJ7
 AQJ65
 J876
 AKJ876
 A
 T9
  T9
 QT9
 65432
 432
  KQ32
 432
 T98
 K87
Dealer: West    Vul: None   MP Scoring

West
21
Pass
Pass
Pass

North
X2
3
5

East
2
Pass
Pass

South
3
4
Pass

 Flannery On The Fly 

1 5 Hearts, 4 spades, 11-15 HCP
2 No Agreement

Without an agreement as to the meaning of a double of the Flannery 2, North had to
weigh the outcomes of it meaning:
1) diamond lead (no point requirement)
2) a standard 2 bid overcall of a 1 opener
3) a takeout of a 1 opener or
4) a balanced 15-18 with a heart stopper

South's free bid of 3 should show something, just what, opposite the above, isn't clear.
Obviously South wasn't play choice 3 above, for 2 would have been superior.
If North had held a heart stopper, then with 3 hearts in hand, East's bidding hearts seems very unlikely so choice 4 looks out.
Probably bidding a 3 card suit suggests that that choice 2 was the initial appraisal.
Actually, of course, it was simply choice 1 with an extra couple of aces, maybe really a choice 5.

When South didn't double or try 3N over North's 3 cuebid, yet bid a new suit (4) suggesting extras, North revalued and risked 5 of the new intriguing denomination.

PLay was routine and South made 5 on the pedestrian top heart honour lead rather than cashing the A and underleading AK to East's Q for a contract setting diamond ruff.
How would you signal as East to help out an A leading West? If West holds not the K...

Playing the 2 would show the A, the 3 the K, the 4 the Q and....and...