It may work for some, but for sure it wouldn't work for me. For one thing, I'm incapable of being sexually interested in more than one man at a time. (Crushes obviously don't count.) That's why I could never date using an online dating service. I tried before I met my husband, but I couldn't deal with the guys who had other dates lined up that week, never mind those who had other dates for the same evening...
One-sided can work too, but only if the parties are very incompatible sexually. Say one wants sex at least twice a day and the other is happy with once a month. Having external relations might save the marriage.