That would be hella confusing if you ask me. Yellow numbers mean that the individual damage displayed was affected by your crit multiplier. For demonstration purposes, imagine that you have these stats: 100 damage, 100% crit damage, 100% area damage.
You will crit for 200 damage, which will be displayed in yellow. If AD also procs the game will display 200 damage with white numbers on the surrounding enemies. Makes perfect sense. You have 100% AD, so you\'ll do 100% of your 200 crit damage as AD.
Now imagine if the game would display AD as yellow when it was based on a crit. You could easily think that AD originally did only 100 damage and did 200 in the end only because it was also a crit. It can be confusing, since the game doesn\'t say anywhere that AD cannot include critical damage. In fact, AD\'s tooltip only states that it does x% of your damage. Not weapon damage, not skill damage, not critless damage, just damage. To me that implies that it\'s based on our final damage, although it would probably be a good idea to state this explicitly in the tooltip.