We don't have enough to invite but we want to keep bidding open in case partner has 16-17hcp.
That being said I think Fred's argument is more important. We are just giving away equity by choosing inferior ♦ fit instead of ♣ one.
My opinion is that this is another sequence which shows weakness of classical systems. 11-17 range is just too wide here. You will have some awkward guesses and this hand is as close as it gets. It's even worse in "standard" american systems (no gazilli, so no intermediate jumps with 5-5) because partner may have real powerhouse here as 3♣ is game forcing.
Note how much better this situation is in precision. We know partner don't have great 15 with 5-5 (cause he would open 1♣ or jump to 3♣ depending on style). We know we have at most 23hcp combined and we have easy pass. Same goes for most 9's hcp hands leaving narrow range for 3♣ (good 10-12).
My vote was pass but I forgot about possiblity of strong 5-5 in partner's hand (I am too used to precision or polish club when it's not possible). I now agree that 3♣ at imps is probably better. We will be often in inferior 3NT after that but I hate missing games
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