Not trying to be snarky, but if you can't find a place to switch scenes smoothly in a song you're probably overplaying. Any song I've played has had some point where there is space to switch scenes or engage/bypass a Control Switch going into different song sections. There's no special trick, just be familiar enough with the song to know where these points are.
Some songs may take a bit of practice to determine the best place to make the change, but there will always be one. If you're trying to cover multiple guitar parts of a recording with one guitar, adapt your playing to accommodate them. If you must have certain guitar parts overlap when using only one guitar live, using backing tracks is a necessity.
I always encourage my team to "own" the song. Practice to the point where you can go through the entire song in your head and play along with it, making no mistakes without any audio aid. This creates freedom in your playing when there is no real thought about the song format or what notes/chords to play. You are able to anticipate each section and progression to the point that it becomes instinct.
This is true... I haven't technically mastered the song I'm playing as if I know it in my sleep from thousands of repetitions.
So I don't OWN it yet. To some extent I agree practice is the most important quality to success, but along the lineside of practicing until your consciously competent, the best player's use tricks up their sleeves to beat out the competition. If you think of the Edge he kept his delay pedal techniques a hidden secret during the 70's , 80's, and 90's when U2 blew up the scene. Only in the recent decade has most of his secrets come out.
I would say play until you can hear the whole song on guitar in your head and visualize every footswitch movement etc. Kinda like see yourself from a bird's eye view as if you're dreaming and can absorb it all.
If there's hesitation at any point you know you have a quirk you've got to iron out before you can be 100% confident.
Just curious do you think playing with backing tracks causes one to forget portions of the songs when they play alone w/o BT? The reason I say this is because with BT's you have some cue's at times... And you can tell by the rhythm if a section is continuing or coming to an end. Without a BT you have none of this and have to rely on muscle memory and your own ability to recall everything.
What are your views on using BT's during recording and live gigs?