Note: The World Wide Web was designed to convey information via "hypertext" -- that is, text with cross-references built in. There is a growing tendancy to use very substantial amounts of non-text material. A picture is worth a thousand words. Unfortunately, on WWW a picture often costs a thousand words, in terms of storage, data transfer time, and rendering time. Some readers will be unable to render graphics in any case. I have therefore refrained from such practices as using gif's for suit symbols. Readers who feel this was the wrong choice should let me know.
An Unassuming Club is a bridge bidding system invented by Donald A. Varvel, although ideas have been stolen from a variety of sources. It is a member of the "Polish Club" family of systems, which in turn are descended from Vienna System, created by Dr. Paul Stern of Vienna in the 1930's. A postscript version of a more extensive document is available.
The distinguishing characteristic of systems in the Vienna System family is a multi-purpose 1C opening. Typically the 1C opening may be of any strength, from minimum opening to game-forcing. In systems in the Polish branch of the family, all three-suited hands short in diamonds must be opened 1C, as well as some balanced hands, and hands too strong for the natural and limited 2C opening. "An Unassuming Club" also includes hands with 5 or more clubs and a 4-card major.
The result is a system with most opening bids limited to at most 18 HCP, 5-card majors, and 4-card diamond opening.Why one more bridge bidding system? There are several reasons. One reason is that the author enjoys inventing bidding systems. Another is that it solves most of the problems of other bidding systems by allowing limited opening bids while avoiding monstrosities like the Precision 1D and 2C openings. Players of 5-card major systems will not need to learn an entire new system, but can use most of the gadgets they are used to.
The name is a play on the "Unassuming Cuebid", which is forcing but not necessarily very strong. The club opening in this system is likewise forcing but not necessarily strong.
The system is based on a 1C opening that is forcing but not necessarily very strong. Another key feature, and one that distinguishes it from most other systems in this family, is its use of a weak or very weak notrump. The version with the weak notrump (12-14) is basic. The second version should probably wait until players are comfortable with the first.
An Unassuming Club ("AUC") uses an unusual 2C opening. A Precision 2C opening is either a club one suiter (6 or more cards) or a club "one and a half suiter" with clubs (at least 5) and a shorter major suit (almost always 4). Even the best bidders in the world have a hard time taming this beast. By adding a few hands to the 1C opening, hands that can be handled fairly easily, the 2C opening can be made much easier to handle. The AUC 2C opening guarantees 6+ clubs and no 4-card or longer major. It is not a frequent bid, but when it occurs it leads to good results.
Because all strong hands (19+ HCP) are included in the 1C opening, 2NT is available as a preempt of some sort. Following Polish Club, AUC defines 2NT as at least 5-5 in the minors with about the strength of a weak 2-bid. Other uses are possible. This 2NT opener is hardly a weapon to strike terror in the hearts of the enemy, but it's useful in its own way.
The 1D opening is limited to at most 18 HCP and at least four diamonds. This is possible because balanced hands outside the 1NT range with the pattern 4-4-3-2 are opened 1C. It is safe to open a fairly strong hand in a short suit because the bid is forcing. 1D is not forcing, and guarantees real length. The only unusual thing is that hands with four diamonds and five clubs are opened 1D. Hands with 5 diamonds and longer clubs are opened 1D, also. (4 diamonds and 6 or more clubs, in the minimum range, is opened 2C, though.)
Major suit openings show at least 5 cards and at most 18 HCP. Practically any 5-card-majors methods can be used. The preferences of the author, and some reasoning, are included, but this material is not basic to the system.