For those keeping score in the battle of the sexes, women got a point last week when a study found that female corporate directors are paid more than males. But since the study also found that women are outnumbered by men in corporate board rooms 8 to 1, it’s probably best to call it a draw.

It’s typical for a study of women in the workplace; there’s always evidence of women succeeding, but in terms of overall numbers, women lag behind. This frustrates feminists who long for women to equal men in terms of total professional prestige. They have numerous explanations for why women remain behind – including sexist workplaces and lazy husbands who pigeonhole wives into keeping house and tending children.

I expected the mother and daughter team, Mary Ann Mason and Eve Mason Ekman, to offer this typical feminist fare in Mothers on the Fast Track: How a New Generation Can Balance Family and Careers. Yet their book, surprisingly, accepted a central premise that’s rejected by much of the sisterhood: most women want to have children, and spend time with those children when they are young. This reality – women’s desire for children and hands-on childrearing – is at the root of why women have failed to catch up to men in most prestigious professions.

As Mason and Ekman detail, the “make-or-break years” for careers (the thirties, which tend to determine if a lawyer becomes partner or a professor gets tenure) coincide with prime childbearing years, particularly for well-educated women, who tend to get married and start families late. As a result, women face painful choices, which sideline many, and thin the ranks of those marching up the professional ladder.

While discussing the “motherhood problem,” Mason and Ekman carefully state that “children are a wonder and a blessing, not a problem.” This might seem an unnecessary acknowledgment to those unfamiliar with other feminist writing, but it’s refreshing after books such as Linda Hirshman’s Get to Work: A Manifesto for Women of The World. Hirshman’s condescending nod to motherhood (she instructs women, “Have a baby. Just don’t have two”) is buried by her disdain for women who stay home with children, and conclusion that even a mediocre career is better than wasting your life raising children.

Hirshman’s brand of feminism doesn’t resonant with mothers, and Mason and Ekman know this. They aren’t attempting to convince women to abandon family for the workplace, but to identify what’s really going on, so that women can better navigate their own career paths.

They dismiss the narratives commonly offered by the media, that women are either “relentlessly rising to equal representation in top positions” or “dropping out at a faster rate than they can succeed,” and offer an alternative picture: “…highly educated women rarely leave their chosen profession entirely. Instead they become caught in a “second tier” within or allied with their profession where they take breaks for family needs but return to work, sometimes on a reduced schedule but frequently full-time, until retirement.” They offer advice to women who want to remain on the “fast track” career-wise while raising families, and discuss how workplaces can become more accommodating, by providing alternative fast tracks and “on-ramps” for those who take time off.

They cite examples of companies that are doing just this: Pfizer, for example, offers working mothers three-day work weeks with the option of returning to full-time. Hewlett-Packard encourages flextime, job sharing, and telecommuting. Mason and Ekman argue that such practices help retain quality workers and are therefore good for the bottom line.

Yet apparently they don’t trust that companies will arrive at this conclusion on their own, and therefore call for government to mandate family-friendly policies. They want the government to require companies to offer paid leave policies and subsidize daycare, and speak glowingly of European countries that have taken these “progressive” measures, while ignoring the high unemployment rates and economic lethargy that always accompany such mandates. Mason and Ekman, like so many feminist writers before them, imagine a world in which men and women are equally likely to utilize whatever parental leave benefits that the government forces companies to offer, but in the real world, women will always disproportionately use these benefits and employers know it.

The flaw in this book is that no amount of advice; and no number of clever strategies, or family-friendly policies will change the reality – those with divided attention will generally not be as productive as those devoted entirely to their careers. Mason and Ekman lament that the vision of the “ideal worker” conflicts with the lives of many working parents. Yet the attributes associated with an “ideal worker” are not constructed to marginalize working parents; they are based on experience of who is most valuable to a company. If companies are truly mistaken – if those who work fewer hours or work from home provide more value in a business sense – then ultimately the definition of “ideal worker” will change, since those companies that embrace this new vision will be rewarded in the marketplace.

It seems likely, for example, that many companies may place too much emphasis on time spent in the office when evaluating employees. Evaluating output will prove a better business model. This will benefit at-home workers, many of whom are women. Yet it seems a stretch to imagine that there isn’t a relationship between number of hours dedicated to a job, and a worker’s value.

An Olympic runner dedicates her life to her sport. In return, she may be rewarded with a medal. Those unwilling to make those sacrifices can’t expect to compete at the same level. It works the same way in the business world; women and men who take time out, whether it’s for family or for another pursuit, likely won’t reach the same level as those who dedicate themselves fully to their jobs. Rewarding some isn’t the same as penalizing others.

Mason and Ekman’s book is an interesting look at the real challenges that mothers face in balancing work and family in a variety of professions. Their tips for navigating these challenges may be helpful at the margin, but no book is going to change the underlying dilemma that we all face in having only one life to live.

– Carrie Lukas is the vice president for policy and economics at the Independent Women’s Forum and the author of The Politically Incorrect Guide to Women, Sex, and Feminism.