Crossword Genius

Behold this clue calligraphy, say? (4,3)

Ross

I believe the answer is:

lost art

I'm a little stuck... Click here to teach me more about this clue!

'calligraphy say?' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'behold this clue' is the wordplay.
'behold' becomes 'lo' (archaic exclamation meaning 'look!').
'this clue' becomes 'start' (I can't explain this - if you can you should give a lot more credence to this answer).
'lo'+'start'='LOST ART'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.
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