Hi, long post, as usual

There is a concept named 'chop focus' which mean that when you give a clue which touch the chop, the focus is on the chop.
With bga's convention, this is weirdly off for play clues (ie if no 3 are discarded, at least one 3 is playable, and you receive a 3 clue, you play the leftmost 3), and on for save clues (ie if some useful 3 are discarded, not all 3 are playable and you receive a 3 clue where one 3 touch the chop, you assume it's a save clue on the rightmost 3).
With hgroup's convetions, chop focus is always on, which mean if at any point you receive a blue clue which touch the chop, the clue would be focus on that chop. (since saves are on with color with hgroup, that mean that it's either a save on that blue card if it's possible, else it's a play clue on that chop card).
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Now let's talk about 'logic' and context, what you can deduce whatever conventions you are using.
Played: b1. Discarded: b3.
It's your turn you discard.
Then your previous player give you a blue clue which touch two blue cards and your chop. No blue are on finesse position.
So firstly, you need to check if others got clues available, and if so, if clueing you was fine or not, maybe there was a lot of plays clues/finesses/saves to do, and clueing you wasn't a priority, even if it's rare.
Secondly, you need to check when b1 was played. Was it recent? Does it occurs after your last discard?
Thirdly, is there anyone which discarded, or who hold a b2 (then it's weird for you to not have clued it). Because if two players got b2, then clueing it can be easily tricky.
So now we removed most of the cases where player would not clue your potential b2 as soon as possible. So let's see others cases.
Forthly, if you discarded a blue card, like b1, then this logic doesn't work. That blue was annoying, and so everyone could have waited for you to discard your blue card to give you a play clue. So let's assume you discarded a non blue card.
Fifthly, if you received b-x-x-b, then you know that in the previous turn you got x-x-b-x and that wasn't clued, so that rightmost blue should not be playable. But now with b-x-x-b, that's still ambigous. With bga, you would assume a play clue on the leftmost card. But if you play with color saves (bga don't, hgroup does), then that could be a save on that rightmost blue too.
Sixthly, if you received x-b-x-b, then in your previous turn, you got b-x-b-x, and that wasn't clued. So you seem to know that the leftmost blue wasn't playable one turn earlier. So if you receive that clue on bga, it could not make sense. You could assume a mistake/something not optimal/you who didn't followed one thing and just play normally, or you could delay that play and do something else which is normal. Note that it's possible even if unlikely that you got r2-b2-x-b2 per example, and so clueing blue now, with a follow up later with 2 can be fine, especially if b3 is visible in another hand. But so with that read you gained a lot of information.
Seventhly, if you are allowed to discard, decided to clue something you wasn't forced to do, and if you received a b-x-x-b clue, then you know that your rightmost blue isn't great. That's more likely a b4 that others didn't cared much if it was discarded or not, but could be a b1 in rare cases (it's more probable if there was an higher blue card on the stacks).
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Now if you change the blue by a number, that's more complicated since there is a lot of colors going on, and if per example a r2 has been played since your last turn, then all 3 clues could be about r3. And knowing if you could hold r3 or not is a lot more tricky.
But chop focus is totally fine, like color saves, the problem is that it increase complexity, and bga try to reduce it a lot.