Hi JustForFun
don't worry about not being able to post regularly - plenty of people just dip in and out - we all have lives :)
As WFF said - you don't owe your dates anything apart from politeness. Some people feel a buzz, butterflies or something, on a first date, other people are horribly let down, other people just feel a 'meh' and think it's not worth a second date.
A lot of dates, though, can be growers - give them a second date and see if they do grow on you. That has worked successfully for some people on here. Mostly though if there isn't a chemistry on the first date it's going to limp on until one of you calls it quits.
Lots of people have said it's a numbers game. I'd be very surprised (although it's possible) if the first or second person you dated turned out to be perfect for you. I'd say give them the benefit of the doubt if date #1 is okay, see if feelings grow on date 2, if not then just let them down gently with a 'lovely to spend time with you but I'm just not feeling the chemistry' text. Maybe you could be friends (it does happen, I still chat occasionally to the Nurse from several months ago) but it's unlikely. But don't waste their time and yours.
On a completely unrelated note, I thought 'cockamamie' was a type of soup?