What is the implication of the question “לימא כתנאי"?

Question

The Gemoro often asks about an argument amongst Amoraim, “לימא כתנאי" Shall we say this is an argument of Tannaim?

I see two ways of understanding this statement:

1] These Amoraim are arguing on the same principle as the Tannaim argued and so there is only one disagreement and not two. (This does not 'criticise' the Amoraim.)

2] If the Tannaim already argued about this case, how can or why are the Amoraim arguing on the same principle – the Tannaim already discussed this. (This does 'criticise' the Amoraim.)

What is the implication of the question “לימא כתנאי"

Answer 1

Halichos Olam 2:1:8 by the Rishon Rav Yeshua ben Yosef HaLevi explains לימא כתנאי as follows:

Is it really true that tannaim are arguing in what an ammora said? It's untenable that an ammora would say something that is not according to all opinions. For if he were ruling like one opinion, he should have said so explicitly. Since he said it in an unspecified way, it sounds like he's speaking according to all. Therefore, the gemarra is surprised and exclaims "לימא כתנאי?!", meaning, this one said like that opinion and this one said like that opinion, and it comes out that they don't agree.

See also K'lala D'Gemarra there by Rav Yosef Caro, who brings relevant sources, and points out that although a difficulty introduced with "לימא" is always rejected in the end, sometimes "לימא כתנאי" stands its ground. See also Halichos Olam 2:2:16 with K'lala D'Gemarra and Yavin Shmuah for more relevant discussion on this.