DHLA 40 Link tube between carburetors

[acalvi]

I rebuilt my DHLA 40 following Des Hammill's useful instructions.
They have a feature not described in the book, a tube connecting the two carburetors on the engine side of the butterflies.
The carburetors came from a Berlina 2000, I plan to install them instead of Solex in my GTV 2000, same engine so Jetting etc. should be OK.
My questions are:
1. Is this a good feature?
2. Will it help balancing?
3. Shall I keep this link?
4. While adjusting should I tap or keep them connected?

[seani]

This looks like a bizarre homemade bodge which I am unsure what the purpose is? A similar result could have been achieved by connecting the vacuum ports of barrels 2 and 3 which dellorto helpfully provided. As the gasket mounting face has been damaged I would take care when fitting the carbs to prevent air leaks.
When tuning the carbs I would plug both tubes initially and only connect them if any idling/balance problems become apparent, the engine will know best.