I also studied "LA MAJEURE D'ABORD", method developed by Jean René VERNES. Strongly inspired by the work of VERNES, I have for several years  devoted my time to develop a more effective method.

What is an effective method?

It does not take a few gadgets inserted here and there. It is first and foremost based on the method that matters.
What does the opening of 1 ♣, 1 ♦ , 1NT mean ...

For example, how to show a balanced hand? It has to be opened 1NT, 2NT or 2x followed by 2NT. As the number of bids is restricted we can not cover all ranges. It is therefore necessary to allocate at least one opening, 1♣ or 1♦, to bid the remaining hands. What is curious in the SEF is that we devote two openings to announce these hands.

However to open all balanced strong hands we do not care whether we have 5 cards in a minor and even  5 cards in a major. So why so much consideration to show a 12-14 HCP  balanced hand?

 

Opening 1♣ all balanced hands 12-14 or 18-20 HCP has several advantages. 

1. The opening of 1♦ is then unbalanced natural .

2. A system of jacoby transfer after  opening 1♣ saves a level for the major fits.

   If we must prospect for a major fit, this will be a step below ( you stop at the 2 level when standard plays 3)

   it Increases your success rate by 30% playing at 2 level compared to somene who plays at the 3 level.

   Could any bridge player refuse such a bonus.

 

Is weak 1NT  12-14 HCP  better than strong 15-17 HCP?  We must know that weak  1NT is twice as frequent as the strong 1NT. The advantage of the opening of 1 NT is first its obstruction effect on adversary and the immediate zoning of the hand. This barrier effect is also its weakness: 4-4 major fit was not detected, unbalanced invitational hands difficult to treat ... The benefits still outweigh.

By cons if we open 1♣ remaining balanced hands in the range  12-14 or 18-20 HCP no problems of rebid if the opponent overcalls.

But in the  15-20 HCP range it's not so easy. From experience, when playing  1♣ opening with balanced hands 15-20 HCP it can be a problem facing preemptive bids. So advantage to strong 1NT.

 

The two level openings in a system requires to be frequent and annoying for opponents.

This can be a partnership deal. The weak two major has to be incorporated. Playing multi 2♦ for these weak hands  is better so you can open 2♥ and 2 ♠ for other hands.

Do you know the openings of two major FANTUNES? These  hands are  10-13 HCP with 5 cards in major and  a shortage or  6 or even 7 cards in the major. These openings require significant work to master the subsequent auctions. They are dangerous, for your side ... sometimes, but more often for the opponent.

Associated with multi 2♦ you have 4 more times  openings at the 2 level.

Another advantage is that the one level major openings  can only be minimum, balanced or with the other major. These inferences are very important to create more accurate developments after a one level major opening.

 

Let's explore the MAJEURE  SECURISÉE.

The goal is to secure partial score and game contracts for all balanced hands with 4-4 or 5-3 major fits. Why play 3 in a major while  opponent is not able to intervene or to wake up. This is because you made a game try.

If the fit is found at the 2 level  while knowing exactly the strenght of the opposite hand, it is not neccessary to prospect at the 3 level,

This is what  MAJEURE SECURISEE does on 1♣ opening (fit 5-3 or 4-4) or on 1 major opening (fit 5-3).

 

 

If one of the hands is unbalanced and in  presence of 9+ cards fit, then prospectives are no longer the same.

Interference and wake up  will be much more frequent. Then we need a more aggressive system which can lead us to the 3 level. "VERNES" law  tells us that we are in distributional security (if we are defeated then opponent has a winning contract).

This is what MAJEURE SECURISEE does  on 1♦ opening(unbalanced) , 1 ♥ and 1 ♠.

 

To follow: 1♣ opening