LAST on HP20S

[jbhp55]

Thanks for the excellent explanation.
I still don't think it works well.

If I continue your example:
60
SIN -> 0.87
2
*
LAST (0.87)
= -> 1.73
+
3
*
LAST (here I'd expect 1.73, but 0.87 comes up!)
= -> 4.33 (instead of 5.20)

It is probably possible to formulate an algorithm to describe this behavior (indeed, that's in the calculator!), but it is not easy to understand for the poor user. So, it's back to STO en RCL for such calculations (or, better still, to RPN)