Slow learners often remember longer because they had to build every piece by hand.

Speed and durability are not the same property. Something grasped quickly is often grasped whole, which works until one piece needs examining and there are no separate pieces to examine. Building it slowly means assembling each part deliberately, and the parts you built yourself are the ones you can take apart and repair later.

If you are the one who needs longer, stop treating that as a deficit to hide. Keep the notes from the slow route, since they are a genuine asset. The real question is what you can still do in a year, and the slow route answers it well.