thing is you can't just make players who don't usually score goals into regular goalscorers - it doesn't work like that
a players personality on the pitch never alters
some players get better but overall you either score goals regularly or you don't
shooting practice will make them better technically but whether they will use it that often is another thing
It's an intersting issue. I think I agree that if you have a system in which all the goals come from two or three players and the others aren't expected to score, and therefore not particularly trained to score, then you probably can't just change that in an instant, like flicking a switch, if the designated goal-scorers dry up.
Playing style becomes a habit; it's the same as the slow-build, passing around the back business - if you set up to do that in the good times, you can't just flick a switch and play with blistering urgency if you suddenly need goals and time is running out. It's either part of your gameplan, and thus training, to be able to switch-up suddenly, or it's not. The same for scoring.
I don't think I agree that a player's personality is unalterable. For some it might be, but a lot can be done via gameplan adjustment and training. I'm not on about technque and skill and ability - those are largely intrinsic - but rather what a player is expected to try and do. But it mosty has to be put into place via the hard hours of coaching and development. Except in the case of a rare, hidden talent, it won't suddenly appear spontaneously from the ether within a game, or even within a bad period in the season.
I guess what I'm saying is that this bad period has shown us that our 'designated attackers' aren't invulnerable to a drastic loss of form, and therefore we need to build-in contingencies for when their goals have dried up.