I'm sitting in first with a very comfortable lead. No need to push anything now, just stay safe. No value in this hand either, I'm actually relieved when right calls Riichi so I have an excuse to bail. I have enough safe tiles too, so it's easy to get out of here.
Left drops 4p.
I call Chii.
Why would I do that? Why am I pushing for a 1000 point Tanyao hand now? Why take that risk?
Simple, because there actually isn't any risk in doing so! I have four safe tiles in my hand: 1123m. Those are my next discards no matter what. I'm fine.
By making this call, I am now 1-Shanten for Tanyao. Even with my next safe discards already pre-planned, there's a path to Tenpai in there. It's not very likely I'll get it, but if there's no risk, then why not leave the possibility open? If it happens, awesome, if not, I drop 123m next. I'm not really pushing here.
A better way to look at this call is that it's just preferable to drawing a tile. I simply don't want to draw right now, so that's why I called instead.