Actually we dont get any worse at defending set pieces. We have been quite sometime if you ask me. And we seem to have forgotten the basics. Or is that what you said? Anyways, I dunno about you, but I think the way we lined up last evening, showed our ignorance to deal with the space that we allowed around the Cardiff players.
(snip)
You're assuming we're man-to-man marking, though? If we were supposed to play an offside trap (which the ranting and hand signals of Sakho while the free kick was being prepared would suggest), then nobody is really marking anybody - they keep an eye on them, but the key is to keep squeezing, hold the line on the kick, and step out. The line is being made and players have to be seen, but nobody is really supposed to mark anybody. Which again, tells me that we don't work on these things in training, because confusions such as that are easily cleared up after a few reps.
Lets look at the kick again, in three frames.
Frame 1:
We see as the kick is being prepared, that Sakho is gesticulating across the line. In the offside line are (1) Kelly, (2) Skrtel, (3) Lucas, (4) Henderson and (5) Sakho.
Frame 2:
Here we can see that Skrtel has pulled up to the line, and played Campbell into an offside position. At this point, all is rosy, and all we have to do is hold our line on the kick, or even step out, if we're brave:
Frame 3:
But Skrtel loses his nerve, and as the ball is being kicked, makes a dash towards the goal that puts every Cardiff player onside, and removes any doubt from the official's mind. Remember, when you run the trap, you are relying on a third party playing along, which is why hands-raised and verbal calls are synonymous with offside traps. Skrtel broke the line, and this made the two players behind Sakho dangerous and legitimate threats as the ball was kicked, instead of being players interfering with the play and forcing an offside call.
This is an easy tactic to get right but it needs many repetitions on the training pitch, which the team clearly didn't have. It also needs one more part of it to be most effective, and that would have negated Skrtel's need to move on the kick. Sterling and Allen are standing marking nobody - they could have acted as counter-runners, so as the line steps out, they are making tracking runs, so that any missed call is at least mitigated by oncoming pressure.
Mignolet is very, very, very low down on the "liability" totem pole here. As with everyone else, he probably expected a disciplined offside trap and was caught short by Skrtel's run. This one was on Skrtel in part, and on Rodgers for probably a greater part, because there is no need for professional players to be that disorganised on a trap, unless it's something they haven't worked on much in training.