I agree with the “blow off the State of the Union”. It’s become nothing but a big photo op for everyone and is no longer productive. Empty seats would be an effective means of protest.
No, the idea isn't to "blow off' the SotU, but to not invite Obama to give it in the first place. There's nothing, other than tradition, that says that the Speaker of the House has to invite the President to give the address - and the President, like anyone else not a member of the House, cannot simply just show up without being invited.
Te only requirement is that "from time to time" the President must submit a SotU to Congress, which can be done as a written report and need not even be annual.