I can't really speak for the 750 motor as I have a 900 but they're not a million miles apart other than the 900 having a few more cc's and a sixth gear.
As with any engine, but particularly a reasonably large capacity fairly low revving single or twin cylinder one, the worst thing you can do is over rev them through the gears or let them labour by demanding large throttle openings while in a high (the wrong) gear at very low revs which manifests itself initially as the snatchiness you felt in the drive chain while riding.
Doing either will accelerate engine wear and use more fuel.
Light engine loadings in the correct gear will give better economy and be a lot kinder to your engine and transmission.
Incidentally, despite having to adjust the 'slack' out them, chains don't actually stretch they simply wear- the 'stretch' is actually increased play in the pins making them 'longer'.
This is quite an interesting read if you want to know more about chain wear, care and see just how many moving parts you're putting a fair bit of demand on every time you ride your motorcycle.
https://www.scottoiler.com/motorcycl...Workshopv1.pdf