Twisted frames corroded, left in a pitiful way (10)

I believe the answer is:

wretchedly

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'in a pitiful way' is the definition.
(I know this)

'twisted frames corroded left' is the wordplay.
'twisted' becomes 'wry' (I've seen this before).
'frames' means one lot of letters goes inside another (outside letters frame the inside letters).
'corroded' becomes 'etched' (I can't justify this - if you can you should believe this answer much more).
'left' becomes 'l' (common abbreviation).
'etched'+'l'='etchedl'
'wry' placed around 'etchedl' is 'WRETCHEDLY'.

Can you help me to learn more?

(Another definition for wretchedly that I've seen is " Miserably".)

I've seen this clue in The Times.

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