When I watch petanque singles matches on Youtube, or play singles myself, I always find myself feeling vaguely dissatisfied. It feels like each mene (end, round) is over before it has properly begun. Or— each mene is being cut off prematurely, before reaching proper completion.
The problem, I think, is that the FIPJP rules specify that, in singles games, each player plays with only three boules. And what would solve the problem, I think, is for each player to play with four boules— 4-boule singles.
The notion of 4-boule singles is a natural idea, and it isn’t a new none. At the FIPJP world championships in Spa, Belgium in 1959, singles games were played with four boules.
Most players find the notion of 4-boule singles an appealing one. In 2016 BOULISTENAUTE.COM conducted an informal survey of world-class players. You can find it on Youtube, in a video called “Pétanque le TaT à 3 ou 4 boules? Interviews”. By a ratio of 2 or 3 to 1, top-ranking players said that they would prefer to play singles with 4 boules.
And of course the idea has a pleasing mathematical regularity.
3-player teams ==> 2 boules each 2-player teams ==> 3 boules each 1-player teams ==> 4 boules each
The bottom line is that in my opinion the FIPJP rules should be changed to specify that singles games are to be played with four boules, or at least to specify that singles games may be played with three or four boules.
Until that happens, nothing is stopping us from playing 4-boule singles in informal/social play. The rules of Petanque Libre, which are designed specifically for use in such games, allow players to play singles with whatever number of boules they wish, and actually specifies that singles will be played with 4 boules.
FIPJP rules specify that in singles games players play with 3 boules. PL rules specify 4 boules. This is a deliberately provocative specification, designed to encourage players to make a conscious decision about how many boules to use when playing singles.
As for practical considerations… petanque boules are normally sold in sets of three, but I don’t think that this is a serious impediment to the practice of 4-boule singles— we can simply play with boules from two different sets. Most serious players own at least two sets of boules, and, for more casual players, sets of leisure boules are inexpensive. And FIPJP rules do not require that all of a player’s boules to be from the same 3-boule set.
The Rules of Petanque 
I like the idea of four-boule singles but I suspect many wouldn’t like the change.
The boule industry would certainly like the idea.
I don’t see the “mathematical regularity” because the idea is to end up with 12 boules (or 6 in single-team plays). If you want that kind of regularity you need
3-player teams – 2 boules each
2-player teams – 3 boules each
1-player teams – 6 boules each
Here is why IMHO three boules are best: with three boules you must be able to play a good point in a 2D space.
First boule can be (eg) too far. Second boule is used to adjust – and it can be (eg) too close.
Now you have enough information to land the last boule exactly where you want it to be (by interpolation).
In my opinion games with 6 boules per team are from a tactical point of view more interesting than games with 3 boules per team. I also think that this is the main reason why most players prefer playing in doubles and triples, and why the discussion about increasing the number of boules in a single game is started.
The proposal to play with 4 boules in a single game is issued in the “Petanque Libre” project but, again to my opinion, not very well substantiated. A choice for 6 boules is more logical as it brings a single game to the same tactical level as doubles and triples.
The only difference then is the fact that all boules are played bij 1 player, instead of 2 or 3 players..
Additional advantage is it simplifies he rules: “Petanque is played with 6 boules per team; a team consists of 1, 2 or 3 players”.
An additional advantage is of course that boules are sold in sets of 3.