[MarkDean]

Suppose you and a partner decide to play two different systems depending on vulnerability. System A is precision with 10-12 nt, and system B is 2/1 with 15-17 nt. It seems clear to me to play A white/red and B red/white, but what would you do white/white and red/red? Would it matter if it was a pairs or teams event?

[awm]

My experience has been that the 10-12 notrump works well when we are NV and not so well when we are vulnerable, regardless of the opponents vulnerability.

The issue is not that anyone is going for "big numbers" very often -- in my experience it is unusual to open a 10-12 and be penalized for more than the value of the opponents game and it is also unusual that the opponents go for a huge number.

What happens more frequently is that the "wrong partial" gets played somehow. Either we play the hand when it belongs to opponents, or one side or the other misses a 4-4 major fit, or the opponents overcall into a 5-1 fit, etc. At vulnerable it's not uncommon to go for -200 when the normal result is something like -90 or -110. These losses add up even at IMPs!

So I think I'd play the precision system at white/white and the 2/1 system at red/red.

[jdonn]

What I used to do when I was young and crazy enough to bother doing such things was essentially this, which you could probably adapt:

w/r: prec, 11-13 nt
r/r: prec, 14-16 nt
w/w: 2/1, 12-14 nt
r/w: 2/1, 15-17 nt

So always a weak notrump not vul and strong notrump vul, and always precision when the opponents were vul (less interference) and 2/1 when the opponents were not vul. I couldn't remember the specific situations, but I could easily remember the logic and re-figure it out each deal.

[MarkDean]

jdonn, on Dec 30 2008, 10:06 AM, said:

What I used to do when I was young and crazy enough to bother doing such things was essentially this, which you could probably adapt:

w/r: prec, 11-13 nt
r/r: prec, 14-16 nt
w/w: 2/1, 12-14 nt
r/w: 2/1, 15-17 nt

So always a weak notrump not vul and strong notrump vul, and always precision when the opponents were vul (less interference) and 2/1 when the opponents were not vul. I couldn't remember the specific situations, but I could easily remember the logic and re-figure it out each deal.

Did worrying about what system you were playing each deal seem to impact your concentartion level?

[Cascade]

Our system is dependent on vulnerability and position although the openings are still natural in all positions. The differences are primarily in style of openings and responses (more than just Drury) and 1NT ranges.

I find that this enhances your concentration as you need to be aware of vulnerability and position on every deal.

[jdonn]

MarkDean, on Dec 30 2008, 01:23 PM, said:

jdonn, on Dec 30 2008, 10:06 AM, said:

What I used to do when I was young and crazy enough to bother doing such things was essentially this, which you could probably adapt:

w/r: prec, 11-13 nt
r/r: prec, 14-16 nt
w/w: 2/1, 12-14 nt
r/w: 2/1, 15-17 nt

So always a weak notrump not vul and strong notrump vul, and always precision when the opponents were vul (less interference) and 2/1 when the opponents were not vul. I couldn't remember the specific situations, but I could easily remember the logic and re-figure it out each deal.

Did worrying about what system you were playing each deal seem to impact your concentartion level?

Hard for me to answer since my concentration was generally quite bad anyway at that age. But it does have some merit, so if you really find that kind of thing fun then go for it. Just make sure you are willing to discuss all the systems.

[dake50]

Y'all got it backwards for IMP. OPPONENTS vulnerability is determinant. They vul means their game decision only need be 10-6 IMP about 40% after factoring doubles in. How likely are they to misbid/underbid a 40%+ shot? Whereas nonvul opponents need nearly 50%. Now obstruction may pay!

Look at 1NT. they nonvul =90/-1=50/-2=100 are all good for them. Get in there!
They Vul at least can hope -2=200. Especially bidding a good lead suit trades 200 for 110 in 2M. Have distribution, poor lead, few entries to compete.

True safety is more a concern we Vul vs nv/, but the payoff in messing up their decision that must be 50% balances this.

[helene_t]

What Josh says makes a lot of sense but personally I am too lazy to discuss more than one system per partnership.

[Fluffy]

Its impossible to know what the perfect system is, but I am sure it depends on vulnerability.

Maybe in 150 years the computers are strong enough to compute all hands and come with a perfect system (but it would only be playable by computers).

Ok a bit off topic, sorry.

[rbforster]

I agree with those who've said weak NT makes the most sense (to me) when we're NV regardless of their colors.

As for memory aspects of playing different systems when vulnerable, they aren't too bad. You were looking at the vulnerability before you bid anyway, right?

[mycroft]

When I did play this, (originally as a joke, but we kept it because it worked well) we played effectively what Josh suggested (although it was 11-13(14) NT throughout, as that's what we were comfortable with): precision when opps are red, 2/1 when opps are white. And for exactly his reason.

We eventually dropped the 2/1 and played precision throughout; it was just easier than pre-alerting and keeping switching the card over.

Although I do remember a pair who played K/S in first and second, and a very sound "standard" system opposite a passed hand.

Edit: Now, I play precision with one regular partner, but we play 10-12 with 2-way Stayman NV and 14-16 with 4-suit transfers V. That's almost harder to remember than switching whole systems, and keeping the NT range (and responses) identical...

[roghog]

Interesting question. How about if your two systems are Strong Club and Polish-style Club?

[Apollo81]

I would play precision at equal colors because I think it is a fundamentally better system, and the chance of getting a bad board from strong club interference is much less than if the opponents were favorable.

I'd stay away from vulnerable weak notrumps -- in my experience they generate lower scores on average than strong notrumps; I don't think notrump range matters much if non-vulnerable.

[ICEmachine]

Personally I think its enough to play 2 systems. One NV and one V. Ofcourse optimal you would like so, but I think because of memory strain and because of extra burden to players having to learn new things instead of relying on their subconscious to just decide more or less for them...

I really like to play strong clubs systems when opponents are V. as its not as easy for them to overcall without risking more.

Right now for easy to learn and very productive systems I would pick

ETM spry when NV and ETM Gold or Victory when V.