This is possibly true. He has also spoiled any chance of Mary Davies or Sean Gallagher having a chance at winning, they'll get squeezed. They should drop out now to save some money.
McGunniess will just say sure wasn't Dev in the IRA when asked about his IRA past and he has a point.
The IRA of the early 20th century did not:
1) Bomb indiscriminately with vague warnings or none at all. Even De Valera cracked down on the IRA when they began a bombing campain in the late 1930s.
2) Target Protestants because of their religion
3) Engage in punishment beatings or kneecapping. Michael Collins specifically opposed this
4) Engage in Proxy bombings
All of these and more occurred during the troubles under direct orders from the IRA army council which included Adams, McGuinness and Ferris, and some actions were carried out directly by them.
If you are prepared to forgive them for that then fine, but I wish people would stop using the early 20th century IRA to compare. I've often seen Gerry Adams compare himself to Michael Collins and his comrades, and nobody seems willing to challenge him on it or tell him the difference.