(ETA description not appearing properly - P's NT is 11-14)
As my team was self-destructing at Brighton, this hand came up (IMPs scoring).
W's NT can systemically be any 5422 or 4441 in the range.
When I asked S for an explanation of the 2D bid, he became quite flustered, and couldn't remember (despite the fact that they'd been discussing it about 30 seconds before, unfortunately, while I'd been focussed on recording the previous score - he was quite elderly). After a fair bit of thought he bid 3S, and N pulled fairly sharpish to 3N. She then said to me that 2D had shown a single-suited major hand.
What would you lead (ETA and why)?