The Meaning of Life, the Universe, and Everything.
Every time I ride a Minecart, A horse/Donkey/Mule or any other ridable thing in the game it feels like some learning to drive stick shift for the first time it keeps starting and stopping. It is very annoying. Is there something I am doing wrong?
I have a regular vanilla survival server on a gaming PC that has 16 gigs of ram, A Nvidia GeForce gtx 760 with 2 gigs of video ram, an Intel i7 processor, and a ssd c drive and an hdd secondary.
This is a common occurrence in Minecraft, in which your movement is updating so fast that the game can't keep up.
You can solve this by slowing the minecart down or using Optifine and raising the amount of time it takes for the game to auto-save. (the latter I haven't actually done, it's just a theory I came up with while typing this :P)
So no, your doing nothing wrong as far as I can see, it's just Minecraft being Minecraft.