You will not learn anything from "what's the time?" opener unless you have the courage to break off the mundane topic. Also girls will not appreciate you "tricking" them into stopping and will often walk on as you try to transition. Better to actually communicate your intentions so they know what's up i.e. "Hey, I just saw you and wanted to say hello cause you look a bit unique from all the other girls I've walked past today" something like that will either get you a rejection or a solid hook. If you get a rejection it will be a "man's rejection" and you will feel better for communicating your true intentions. If it hooks then you can see how far you can get (maybe instant date or number..even instant pull is possible..think disabled toilets of coffee shop ). What I am saying is low-risk openers will not help you to learn, in-fact they will discourage you as you are not even in the game as your intentions are not known. It also puts more pressure on the approach which is a good thing as you build mental stamina and "balls", a key component of game. Trust me I have tried low-risk openers and they just don't work.

Pickup is mostly a numbers game. Some girls will be into you, the majority will not. It is your job to identify the girls that don't like you and invest in the girls that do. The determining factor being persistence and not taking rejection personally. Their initial reaction will tell you everything, if their eyes light up you are in, if they scowl you should give statement of empathy i.e. "I know it can be super annoying when some guy approaches you but I was really interested to see what you were like" if she still is off, then say "we'll I gotta go, nice to meet you, ba bye" and that's it. On to the next one, making sure to minimise time between sets, so your brain can't process the rejection and your state stays up.

This stuff is hard. There is no easy way around it, which is what you are looking for. With that in mind value action over everything else. What happens after the approach is irrelevant. But you must state your intention on the approach, or a second best approach would be to make them laugh through a funny observation (best in a group setting). You put yourself out there, stated your intentions and got the response. At the end of the day you revise what you did, how much resistance to approaching you felt and gauge your progress through this measure, not your actual results (as these are unpredictable).

Hope this helps and obviously everyone can make each method work for themselves, I am just giving my opinion.