To open 1N or 1  that is the question
   


First make certain that NO other BETA opening bid other than 1 or 1N is appropriate - if there is then one must prefer it and never choose either 1  or 1N.
Now a decision between 1 and 1N must be made. If 1N satisfies all rules then it must always be preferred to a 1 opening.
In the case of 1N after making all necessary HCP adjustments. BETA uses only a 12-14 1NT opening.  In beta good 3rd hand 12-14 1N openings are encouraged BUT we will not shade to 11 HCP.
BETA's 1 opening is usually 12-18 but maybe shaded to a good 11 in third or fourth opening positions. With 18+ prefer a 2 opening]

The distribution restrictions on our 1N openings must be adhered to in all positions these are:: No 5 card Major or Diamonds, No void or singleton, at least 4-3 in the minors, a 3 card minor must be headed by one of A¦K¦Q and allowed distributions are 2245, 2236, 33{43}, {24}{43},  {23}44,  {23}35.
So we prefer 1N whenever we can instead of 1♣ with the mild pre-emption it offers. The theoretical reason for this preference is that the IN opening may contain a single 4 card Major about 20% of the time with a distribution of {24}{34} - an ideal 1N distribution. So are {23}44 & {23}35.
Now {34}{33} hands are always opened 1 and any of the above mentioned that fail the Hxx test in a 3 card minor are also opened 1.

The limitations Beta places on a 1N opening are aimed at practically making a safe minor suit exit from 1NT * as partner can bank on finding at least 3 card minor suit support with transfers of ** for 2 & 2 for 2.
A 2 inquiry can be made to obtain detail of the 1N opening with high precision: 2Ma: 4 cards; 2D: 4 cards; 2N: 4 Clubs and 3: 5|6 Clubs
These restrictions  have reduced the % occurrence of a 1NT opening in BETA to be significantly lower than its occurence in ACOL. On the plus side a significant increase in the frequency of a 1 opening - this fits very well with the mathematical  'theory of information' - and Beta uses this advantage to its limit. See our 1 opening for full details.

The importance of our 1NT  opening lies in  its reduction of the frequency of 1 openings.