Shorting as an activity is extremely hard to make money on, as...

Shorting as an activity is extremely hard to make money on, as unlike with long positions, time is your enemy as you have borrowed and are paying interest. Like derivatives, it is extremely hard to make money as you are to a great extent dependent on market timing to make a return. [See Buffet's bet on the

That is not the full picture as scale also plays a part and the herd can generate additional momentum to make a play profitable. ACR has been a good stock to play with and with all things some market shorters tend to play for longer than they should in some stocks. ACR volatility has been extreme since the FDA started having a look and has been well shorted with all the question marks surrounding performance. That seems to be largely played out as regards the dangers of TST and with the stock trading in the bottom quartile of its 3 year range ($1-$4, 4th quartile up to $1.75) is not in a great position for shorting and hence we see the largest players moving onto their next victims.
As with everything, it sometimes takes people longer than they should to move on. You'll also note the deafening silence from the baggers when the SP rises, e.g. in December and January when the price rose 60%!. It will consolidate a little now (as the shorters try to panic you out) before it's next upward phase driven by strong sales, a milestone payment and a weakening AUD.

ACR is a great little company with a good product and technology and with sales in the mighty US dollar, AUD revenue has gone up by 20%+ anyway, although USD sales were strong in the quarterly and showing no signs of an FDA induced panic.

As always DYOR