Mercury Retrograde may not have any mental bearing in most peoples daily affairs but the effects are true to form every time Mercury passes between Earth and the Sun three (sometimes four) times a year. And Mercury is the winged messenger which rules communications, and includes any man-made electronic device used in communications.
Mercury's frequency, when it lines up between Earth and the Sun, has enough influence to interfere with normal operations and things will not go as planned no matter how hard one tries to push or fight to have their way, forget it, just wait till Mercury finishes passing by.
Anyway, just as the Sun brings us life, the Moon controls our tides, it is Mercury that controls all communications. The point being here is Mercury Retrograde is coming up starting May 7th, at 1degree Gemini 22 minutes, so April 20th will not be effected by adverse effects of Mercury like what happened in January 2009.
http://www.astrologycom.com/mercret.html
The most common phenomonen surrounding Mercury Retrograde is the advent of doing things twice, starting over later/again, or taking twice as long to complete because of the actual frequency interference the planet causes- similar to say how sun spots may create static or blank outs.
Oddly, Mercury will be direct or through passing in front of Earth on Sun May 31, at 22 degrees Taurus 52 minutes, but still takes a few weeks for the energy to become normal again. So whatever is going to be done more than likely will be done before Retrograde or it will be intereferred with of natural phenomonon. Mercury is always the fly in the ointment when someone does not realize its relevance.