It seems the cry outside of Dallas (mostly from Giants, Skins and Eagles country) is that the gap has closed between those teams and Dallas, largely to the "drop off" at OL for Dallas.
I tend to think that's wishful thinking. For one, it's hard to imagine an OL that has arguably the best LT, C and OG in football would go from being great to blah because you had to replace an underperforming RT and a good LG. Second, people seem to forget that Collins was thought of as a first round RT talent. If he's as good as his scouting reports coming out of college showed, this OL might very well be better than last year's.
If you are getting elite play at LT, C and RG along with good play at RT, frankly, if you get even average play from your LG, you are going to have a dominant OL.