I have seen ERHC management put out info. So when they don't, investors (as you say) are left to speculate. Often the speculation is not correct. By the time some board posters get done with the speculating, management has no chance matching the expectatitons.
For myself...I assume that when no info is being released...there is no info...nothing new. Everything in this business takes longer than expected to occur...and it's even worse in places that ERHC does business.
I remember the news that ERHC had begun the inquiry into an AIM listing...remember how that turned out? If management were to make public every attempt to move forward...and every result...investors would most likely be complaining that management was manipulating the sp. LOL.