I know you said "Forget those pictures", but my red pen just could not ignore them

Sorry
Click to view attachmentThe circles show bad splineage.
Click to view attachmentWhere you have 5 lines coming into one point, that is bad in spline language. It is better to create 5 point patches, and use the 5 point patch tool to fill in the patch.
The "spline continuity" picture is using the comma , key. This is a marvellous tool to find out whether your splines are continuous. Click on a spline near the control point, and press the comma key. All cps on that spline will be selected, and show you where your spline is ACTUALLY going, rather than where you THINK it is going.
Then you use the K key to break the splines where they are not correct, and reattach them correctly. Sometimes in reattaching you have to lay down a 'fake' cp, so that you can get the spline to flow in the right direction, then delete the 'fake' cp.
I have circled the one at the bottom left, even though it looks right. Because of that little bit of black, something is probably wrong in that area. The comma key may show discontinued splines, or it may be 'normals' facing the wrong way. Press Shift 1 and you will get normal pointers - you can then check to see that all points are outwards. Then press Shift 1 again to get rid of them. (That's the 1 key NOT on the num pad.)
It all takes time and study, but you're almost there. Then splines become so much easier.