This question was posed over in a post at IMDB and got mainly the answer NO. Let's see what Trek BBS says. Okay, when you have series with sci/fi elements it is inevitable that time travel is going to show up sooner or later. Should SHIELD do the obligatory episode? I would be fine for it as long as it is just a one off episode where they are unable to duplicate the method of time traveling so as not to milk it to death the way STAR TREK went to that well several times too many making it less special so to speak. Time travel "One Off" storied CAN be excellent. I would like to point to what was arguably the best episode of the 1990 FLASH series. Trying to outrace a missle the Flash was blasted through a hole in the space time contimum ten years into the future. To get home and reset the timeline STAR LABS's nuclear reactor was detonated to reopen the fissure in time. It really was a great episode seeing FLASH in the "future" of 2001 with the usual dystopian society and everyone knowing that Barry Allen had been the FLASH> Handled right SHIELD could do an excellent episode...for instance COULSON could be sent back and try and stop his hero CAPTAIN AMERICA from being frozen for 70 years.