By 'Tough Enough' are we strictly speaking of fighting and retaliation? If so it must be taken into account that the Flyers have almost always been at a disadvantage in the NHL with the Officiating due to past sins and reputation... They Flyers have to play expecting to still, after all these years, be under the microscope and get some calls that other Teams would not. So, often coaches such as Berube -- and I'm not by any means defending Chief or making excuses for him here -- pull back on the reins and coach the Team in a manner where they pay attention to not playing too much at a disadvantage... And it must also be pointed out that in the Current Cap Era the Flyers have chose to carry more skill role players on the lower lines rather than carry a 'Heavyweight' 'Enforcer'... feeling that in Today's NHL one is not really needed.
But 'Tough Enough' can also be associated with intestinal fortitude and the ability to play in rough situations and hold one's own rather than be muscled away or intimidated off... and to keep on going into the corners against the bigger and tougher opposition without fear... or standing one's ground in front of the net or going there to clear it. The ability to tough it out and stay in games that seem lost rather than tuck their tails between their legs and accept defeat without going the extra mile trying to dig out of the unsurmountable hole.
The former Tough situation is understandable and must be dealt with... the latter Tough situation is where I believe Teams such as the Flyers must be questioned... in in the latter one also is the ability and desire to stand up for Teammates.
It seems to me that the Flyers have always sought after in the Draft, via trades or in Free Agency the stereotypical Flyers Type Player and draft the Downies of the or seek out the Carcillos via trades or the many Free Agent tough guys that have paraded through the Organization over the many Seasons. I agree with the person who mentioned that Ryan White is the type player that the Flyers must look to to instill that needed toughness, and still stay competitive in the faster and more skilled NHL of today... Forget the loose cannons that always seem to get the Flyers in trough, digging the holes that sink the Flyers in the end... pass on the next Steve Downie or Dan Carcillo and seek out the available Ryan Whites who demand lower Cap Hits and provide disciplined toughness and give more bang for the buck.
In the end though, IMO, it is the Teams that can compete in all manners... speed... skill... muscle... perseverance... smarts... desire... willingness to go the extra mile... that are able to stay in the hunt against all competition Season after Season. All the Teams that fall short of that balance rise and fall depending of who they draw and pray for the right matchup and ultimately go down pretty early, if they every even make it... Look at the Dynasties before the Cap when there actually were some, and you will see Teams like the Canadiens of the Seventies who could skate with the best and duke it out with the best... To a lesser extend the Bullies here while being noted for their brawling, actually had a balance along with their toughness and had many skilled players with their many role players and a coach like Shero who knew how to get the right mix... and a GM like Allen who could get them the horses.
But that does not answer the question I guess. LOL... oh well.