You might want to be carefull with those techniques.

The way they save code space is by bypassing the normal Bank switching, and Code Page changes that PBP needs to keep track of, to continue working correctly. Under the right circumstances they can indeed save Code Space.   But, just at the time when you "Need" to have the program working, you'll be chasing bugs that seem like they "Just can't be happening". He hints at the problem with a "NOTE:" but I think it's more serious than that.   Especialy with large programs. A.K.A. Harder to Debug.

Granted, others are valid, like separating "ANDed" IF statements etc. But, bypassing PBP's internal processes can be risky.
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