What's your explanation/evidence

I like this sort of question. Based on my own field experience, I agree with wedrifid's advice. Also, it's not hard to delay sex a few weeks, especially if are only going out with the person once a week.

• Day 1: meet, exchange numbers, kiss goodnight
• Date 1: make out for a while
• Date 2: make out for a while with hands roaming
• Date 3: make out with some clothes coming off, dry humping, maybe one or both people get some manual stimulation
• Date 4: oral, manual
• Date 5: sexual intercourse

Spread out with a week in between, these 6 steps could take 1.5 months to complete. In my last relationship, the schedule was something like this, and it didn't feel unnatural. It also helped that she liked to initiate things, so that I knew that she would initiate sex when she was ready; then I didn't have to try to guess the right timetable for sex and risk being too fast or too slow.

Of course, some of these steps can be accelerated, and people might meet more than once a week. The point is that it should be easy to delay sex past the two week mark, while still doing more sexually each time.

Don't be hanging out more than twice a week, or more than two days in a row. People shouldn't be doing that anyway in the beginning, because it's a great way for people to get sick of each other.

Have dates be activities where sex is logistically hard. Keep everything in dark corners of clubs, in parking lots, in cars, or out in nature. If the environment is a barrier to sex, then you won't have to refuse it.

See the amazing Playette FAQ:

If you haven't hit emotional hookpoint it yet AND YOU WANT IT, don't put yourself in a situation where sex can happen and then refuse to have sex -- just try to keep subtle control of logistics such that the rate at which you approach a possible hookup roughly corresponds to the rate at which his emotional attraction is growing. If you can't think of a smooth, natural way to delay isolation until you've hit hookpoint, then you have to weigh your options and make a quick decision: would you rather bail on the interaction, or go for it and risk the possibility that you won't hit hookpoint at all? I'd like to stress gently, here, that no matter what there are no guarantees. Some guys can hit hookpoint after sex. Some will immediately before. And some, no matter how long you have with them, never will. In either case, a smooth interaction is key - smoothly bail, or smoothly go with it. In general, I would avoid any kind of 'status of the hookup' talk or obviously artificial speedbump.

The most stylish solution would be to logistically delay sex without it feeling artificial for the other person. Yet if you are dating someone who is nerdy and/or capable of explicit communication around sex, explicitly trying to explain when you do or don't want to have sex could work. And if they specifically ask you when you will want to have sex, or keeps trying to initiate it, then they may force your hand (but if they are playing stylishly, then they shouldn't be trying to make you logically explain yourself).

Explicit negotiation can be very costly, and this cost isn't recognized by people in culture who are always gushing about "communication" and "talking about it." Setting up a date that makes sex difficult subcommunicates that you don't want to have sex, which can often be superior to explicitly explaining it to your partner.