Now, back to my original question. Recreational sex simply because it feels good is forbidden if you are not “open to the possibility”. Now, “open to the possibility” is not necessarily the same as “aware of the possibility.” A couple of newlyweds may want to start a family but not right away. Are they forbidden to have sex (using any means necessary - short of ABC - to thwart a pregnancy?) just because it pleasures them? They may be aware that it could happen, though they would rather it not happen.
From the catechism:
*2368 A particular aspect of this responsibility concerns the regulation of procreation. For just reasons, spouses may wish to space the births of their children. It is their duty to make certain that their desire is not motivated by selfishness but is in conformity with the generosity appropriate to responsible parenthood. Moreover, they should conform their behavior to the objective criteria of morality:
When it is a question of harmonizing married love with the responsible transmission of life, the morality of the behavior does not depend on sincere intention and evaluation of motives alone; but it must be determined by objective criteria, criteria drawn from the nature of the person and his acts criteria that respect the total meaning of mutual self-giving and human procreation in the context of true love; this is possible only if the virtue of married chastity is practiced with sincerity of heart.156
2369 "By safeguarding both these essential aspects, the unitive and the procreative, the conjugal act preserves in its fullness the sense of true mutual love and its orientation toward man’s exalted vocation to parenthood."157
2370 Periodic continence, that is, the methods of birth regulation based on self-observation and the use of infertile periods, is in conformity with the objective criteria of morality.158 These methods respect the bodies of the spouses, encourage tenderness between them, and favor the education of an authentic freedom. In contrast, “every action which, whether in anticipation of the conjugal act, or in its accomplishment, or in the development of its natural consequences, proposes, whether as an end or as a means, to render procreation impossible” is intrinsically evil:159 *
vatican.va/archive/ccc_css/archive/catechism/p3s2c2a6.htm
So to answer your question, it is perfectly acceptable for a couple to have sex for fun as long as they don’t deliberately deprive the act of its procreative end, and have just reasons for avoiding pregnancy at the time.
“Just reasons” is for the couple to prayfully decide. A newlywed couple may have just reasons for delaying pregnancy (eg to finish a degree perhaps) and so can have “recreational” sex - a better way to put it is unitive sex - but must not deliberately rob the act of its procreative nature, through ABC for example or other means (coitus interruptus).
Does that answer your question?