i need a little advice on downshifting. let's say i'm on a fairly long climb. i'm on the middle chainring, but downshifting as the climb gets harder. eventually, i'm on the middle chainring and largest cog, but i need to drop down to the granny ring. (hypothetically speaking, of course!!!!! ) anyway, if i drop down to the granny while on the largest cog, that is too low of a gear and i lose momentum. what is the best way to downshift from middle to granny ring without losing too much momentum? should i upshift a couple of gears in the rear, then downshift the front and adjust the rear as necessary?