This has been on my mind a lot and as a result of a totally different conversation, it got me thinking about the transitive property. If a = b, and b = c, then a = c. Not sure it totally fits but it definitely got me thinking! Thanks for posing a great question!

I know I am a little late to the party but a Rekenrek would work really well for modeling this strategy. Instead of counting back and subtracting 3 from the bottom and 2 from the top, you just subtract the 5 from the top row (which is your 10). Helps visually show why you have to add the 3 back.