I have been lucky to be able to get Doyald Young's two larger tomes "Logos and Fonts" and "Logotypes and Letterforms" from my Library. Hooray for Interlibrary loan! I have enjoyed reading about his fights with spacing issues such as when a logo includes an All Cap "LA" Combination. He sensibly shortens the lower bar of the L. He also explains that it was for even color that he loses the pot hook on top of the "i" in a script "riu" combination. And he extends the lower bar of a "z" with a swash to fill the void of a "v" in "rendezvous". These adjustments are all in logos meant to catch the eye, although each of these adds some optical evenness to the designs as well. I think these books might be instructive for Opentype display type makers with a mind to make contextual alternates, or maybe with some special care - Opentype text face makers as well.