Ah, I see ILang deals with the issue by… not having a name binding primitive, making you SKI-calculus your arguments into place. (Compare the piles of roll-swap-dup you get in varless forth dialects, though not as bad due to there being two directions args are passed in from.)

I suspect there is room here for an unprincipled "preceding word/pattern is defined by the following line/s" loose-binding operator, to restore skimability, and a separate inline destructuring let form that cannot leak out of lexical scope. Which I suppose would warrant lambdas - perhaps with ⍺ ⍺⍺ ⍺⍺⍺ to denote enclosing function input, rather than argument/operand/hyperand, though nonconcrete functions would stress the type system as is