Source: AUSTRALIAN YOUTH BRIDGE BULLETIN NOVEMBER – DECEMBER 2015 
Bergen Raises are a neat little tool that has both constructive and destructive purposes. The main advantage of the Bergen Raise is to let the partnership know of the immediate nine-card fit as responder also shows their point range.
Bergen Raises typically use a jump of 3-minor over partner’s 1-Major opening to show four-card support and either 6-9 points or 10-12 points. Another advantage that this serves is that if fourth seat has a strong hand, jumping to the 3-level will have taken away a lot of bidding room for him. The corollary to that, of course, is that if the opponents don’t have the strength to get into the auction, you will have unnecessarily forced the partnership to the 3-level when an auction of 1M-Pass-2M would have ended the auction.
As a partnership, it is up to you to decide whether the advantages outweigh the disadvantages in order to take up this convention. In the event that you and your partner decide to play the convention, you then ask yourself, which bid shows 6-9 points and which bid shows 10-12 points?
Some people play Simple Bergen Raises where 1Major – 3 shows 6-9 with 4+ support, and 1Major – 3 shows 10-12 with 4+ support. Some people play Reverse Bergen Raises where they reverse 3 and 3.
If you and your partner are wondering which is better, go for the Simple approach. Whilst it’s true that 1Major – 3 will give you a bit more bidding space for slam exploration (which is better(?) utilised for a jump to 3 to show 10-12 points), the fact is, it is more important to use the ‘middle’ bid (3) to ask whether partner is minimum or maximum.
So after 1Major – (Pass) – 3 – (Pass) ; 3 would now ask whether responder is minimum or maximum for the 6-9 point range. You can of course use the same asking bid had 3 showed 10-12 points, but quite often opposite the 10-12 limit raise, opener would be either signing off or bidding game, but opposite 6-9 (quite a large range), it’s more important to find out whether responder has 6 or 9.