Link to Round 5 is here
Link to PMA Round 4 is here
This is a critical point of the hand. At the risk of sounding like a broken record, a lot can change when 10 cards are dealt simultaneously instead of sequentially. Moreover, once the stock is empty the effects of a bad draw can be catastrophic, or we could come up golden and reach a position where it’s virtually impossible to lose (unless all three blobs were impostors) – or it could be somewhere in between.
In this case, we got an excellent draw. The main point in these situations is not to panic at the sheer number of cards in the tableau. Careful analysis shows we can indeed remove one full deck of cards (including the Diamonds that have already been removed) regardless of the permutation of unseen cards. It’s not necessarily the best course of action, but at least we have a fallback if analysis reveals nothing better.
All three blobs wanted to “delay” this decision by not turning over any cards – and I believe IM Bartacus and IM Bug chose the wrong plan. They ended up in the following situation:
If we ignore the fact the newly turned over card in column 2 is a K of Spades, then we have three suits removed and two guaranteed turnovers. Now let’s look at Blue’s suggestion: “id,ai,ai,hi,hf,ha,ei,ea,gi,gj (h12=i8)” leading to this position:
This is much better. We can play fe,df,jd,jh,ie,fi,cg,cb,ci,(e7=h7),bi,ei,be,(b1=h6) to reach this position with four suits removed and also two guaranteed turnovers
No wait – in the actual game we get three suits removed and THREE turnovers. We weren’t allowed to count the fact the newly turned over card is a King of Spades (giving a home for the Queen in column 7) but we can count the fact we turned over something in column 2. This means Blue’s suggestion was not clearly superior to the actual continuation, and the team had every right to believe Blue was the impostor. Rot13(SHPX SHPX SHPX SHPX SHPX SHPX SHPX SHPX SHPX!!!!!).
Blue thought he was being clever, by using the Queen of Hearts in column 8 instead of column 6 (indeed using the Q in column 6 would be egregiously bad) but this turned out to be a miscalculation. To be more specific, the actual game continuation achieved one more guaranteed turnover at the expense of one more suit – and this is a good trade-off because the biggest danger of losing this game is if the next 2 or 3 cards are bad. There is little danger of losing because we removed too few suits.
In case you didn’t follow all of the above the TLDR version is rot13(Fcvqre TZ shpxrq hc).
In the endgame, Blue insisted on clearing the mess in column 8 early to avoid column 8 becoming a problem later. This is a good general principle:
KNOWLEDGE BOMB: From a position of strength, it is often wise to identify a “difficult task” and get it out of the way before it becomes a problem later (remember the dangers of one-hole-no-card).
The situation Blue wanted to avoid was this one:
This image is from the back cover of Steve N Brown’s excellent book “Spider Solitaire Winning Strategies”. When I saw this image, I immediately recognised it for what it was – most probably thanks to playing far too many games on a Spider Solitaire server that I am convinced is biased. If Steve played on that server, I would bet my Ph. D. thesis he would not have written the words “this game could have been won if only a little more care had been taken”.
Unfortunately for Blue, this knowledge bomb turned out to be unnecessary – the simple plan of turning over everything outside Column 8 was sufficient, even if the impostor were allowed to call the remaining face-down cards in column 8. My calculations say that ten columns in the tableau is just barely enough to get the job done (and I fully trust IM Bartacus and IM Bug are more than capable of reaching the same conclusion) and the actual cards were nowhere near the worst-case scenario. With winning reduced to a mere formality, Blue had no chance to redeem himself. He tried to inject a little humour by rapping in the Iambic pentameter but it was all in vain.
In summary, a great game with both Team Good and the Impostor having legitimate chances to win until the very end. IM Bartacus and IM Bug navigated most of the traps but let a few bad ones through, and the position looked desperate at one stage. But we managed to pull everything through in the end – until Blue had an absolute brain-fart, miscalculating a critical decision at the start of round 5 and giving IM Bartacus a good reason to believe Blue was the impostor. IM Bug tried to salvage the situation by explaining that “1 impostor” was written in red font and therefore the impostor should be Red. But my Random Number Generator app would have none of that and Blue was declared the impostor anyway on the tie-break. In the end, honours were shared with Team Good winning 100VP out of a possible 200.