I've done calls before and they talk too much. Phone, text, facebutt, etc. should be used for setting up a date. Not talking for hours. The more you talk before the date the less you have to talk about AND increases the chances of slipping and saying the wrong things.
Nah this is just bullcrap man. YOU control the conversation and how long it is, not them. If you want to get off the phone, tell them you need to run.
And if you are worried about saying the wrong things or screwing yourself over, you clearly need to work on your conversational skills...I talk to women pretty regularly prior to first dates and it always leads to them being MORE interested in meeting not less. Talking getting them to laugh and having fun is a GOOD thing.
If they don't want to meet after talking to you, it's on you for not having conversational skills which means meeting in person is simply going to have things go the same way, but at least you met up.