It would help knowing whether that big Malphite is going tank or ap, so that I'd adapt according to what my team is missing.
Additionally it would allow us to warn allies when they seem to have the wrong mastery (similarly to warning my toplaner who forgot to remove Smite from his previous game)
Cheers 
Lucían Main2 votesYou can always just, you know... um... ask...
Joke aside I'm sick of telling me not to pick Hail of blades on Ashe or Vayne, or even Jax, just cause it's not the most common build. It works wonders for me. So stop judging. Last thing I need is people in champ select going "omg d00d no hail of blades y troll"
wolvius1 votes[{quoted}](name=Lucían Main,realm=EUNE,application-id=3ErqAdtq,discussion-id=3xeX3p61,comment-id=0001,timestamp=2019-09-17T10:45:09.472+0000)
You can always just, you know... um... ask...
Joke aside I'm sick of telling me not to pick Hail of blades on Ashe or Vayne, or even Jax, just cause it's not the most common build. It works wonders for me. So stop judging. Last thing I need is people in champ select going "omg d00d no hail of blades y troll"
Yeah might be a pain trying to explain my predator-sorcery Malphite or glacial sion runes in ARAM lobby or dark harvest trundle when it was league of DH. People can be such assholes.
Leptyx3 votesJoke aside I'm sick of telling me not to pick Hail of blades on Ashe or Vayne, or even Jax, just cause it's not the most common build
Just get used to it :p Main Teemo here (sorry), I get the "don't pick Teemo" since s3, and moreover sometimes I go Phase Rush (against Garen for example). I won't mind if they judge, I prefer reading 99 useless comments but at least I get warned the day I have the wrong masteries
DeathBurst1 votesI would support that if there is a good way to integrate it in the user interface.
Leptyx2 votesDoes it seem like a challenge for Riot ?
DeathBurst1 votesI honestly don't know. I have very low faith in them.