When I eventually get around to changing from triple chainset to double and bash, I guess I'd shorten my chain by the number of links equating to the difference between the old large chainring and the new middle, say 44-36.
Keen to reduce as much as possible as hoping this should reduce the number of times I'm dropping the chain on the downhills.

Sounds obvious I know but is it that simple?
Anybody else's trial-and-error that I can benefit from?

Cheers

Loop the chain around the biggest sprocket and chainring and add 2 links for best chain length.

just do the bigest front ring to biggest rear cog plus 1 or 2 links thing that you always do with a new chain – it'll just be the 36 you'll be using, not the 44.

Just to be clear – the above instructions are to be carried out while the chain is not running through the rear mech – that is why you add a couple of links, to compensate.

Thanks guys. That's plenty clear enough.
I'd always measured new chains against the old ones, rather than as you'd described. Habit I guess – It never occured to me to do it any other way.

Cheers.

…. and a link is 3 rivets worth (and don't forget to allow for a powerlink if you're using one i.e. half a link).