Soft Synth in Track Folder - weird CW Sound Center sound!?

 Hi, I could't find anything on this in the forum:
I created a MIDI track, put in a few notes, routed to the Soft Synth CakewalkSoundCenter to play the patch 'Arabian Nights'. This worked nicely. I added another clip to this MIDI track later in the project. I was dragging this clip closer to the previous one, when my shaky hand accidentally dropped the MIDI clip into the Synth Track Folder precisely one track below the MIDI track I was aiming for, slightly overlapping the previous track's latter time section.
I got no error message, instead, the clip was displayed in the synth track folder, so I hit playback and listened. I was happily confused by the fact that first the Arabian Nights sound came from the MIDI track, and when playback came to the overlapping bit in the synth track folder, the sound changed weirdly, yet enhancingly for the project.

My limited synthesizer/MIDI knowledge tells me, that somehow the synth is playing/warping the synth (I'm aware that soft synths can be used in the fx bin - but I don't understand any details).

Can someone explain to me, what the clip in the folder is doing to the MIDI track, please? Could you also help me to understand this way of deploying a soft synth deliberately, i.e. which synths can be used this way, which synth parameters are well-suited to trigger (if that's what ther're doing) the MIDI track, please? I suppose it's what an analogue synthesizer's knobs and wheels do, but I'm a bass player by nature ...;-)