which could have avoided if you had vs which could have avoided if you

Some examples from the web:

• All of which could have been avoided if you hadn't interfered with...
• Of course, you could have avoided this embarrassment if you married the wealthiest man in Qarth.
• The scandal could be quickly avoided if you'll just cooperate.
• But all this could be avoided if you're ready.
• I could have avoided this if the Bob Williams deal hadn't gone bad.
• This whole thing could've been avoided if you didn't try to hide it from me.
• The crazy thing is most assumptions could be avoided if you just asked a simple question in the first place.
• This can usually be avoided if you remain inactive for at least 4 hours after taking Sonata.
• All of this could have been avoided if you people had done your jobs in the first place.
• All this could have been avoided if you just stopped Light instead of chitchatting with her.
• This whole thing could've been avoided If you just told us anything about the sword, the tsuba, your past.
• All of this could have been avoided if you'd have just told the truth.
• This could have been avoided if you hadn't played with something you don't understand.
• Many consider that the crisis could have been avoided if the rules governing banks and credit institutions had been better.
• Best to be avoided if at all possible.
• Many pollution accidents could have been avoided if there had been better safety.
• It all could have been avoided if they just, you know, communicated.
• Lengthy transitional periods for certain Member States must be avoided if at all possible.
• Circumstances that could have been avoided if you'd simply removed your brother from New York as I recommended a few months ago. "Simply"?
• The rapporteur believes that this problem could partly be avoided if electricity was produced closer to the main consumption points, whenever it is possible.

Some examples from the web:

• All of which could have been avoided if you hadn't interfered with...
• Of course, you could have avoided this embarrassment if you married the wealthiest man in Qarth.
• The scandal could be quickly avoided if you'll just cooperate.
• But all this could be avoided if you're ready.
• I could have avoided this if the Bob Williams deal hadn't gone bad.
• This whole thing could've been avoided if you didn't try to hide it from me.
• The crazy thing is most assumptions could be avoided if you just asked a simple question in the first place.
• This can usually be avoided if you remain inactive for at least 4 hours after taking Sonata.
• All of this could have been avoided if you people had done your jobs in the first place.
• All this could have been avoided if you just stopped Light instead of chitchatting with her.
• This whole thing could've been avoided If you just told us anything about the sword, the tsuba, your past.
• All of this could have been avoided if you'd have just told the truth.
• This could have been avoided if you hadn't played with something you don't understand.
• Many consider that the crisis could have been avoided if the rules governing banks and credit institutions had been better.
• Best to be avoided if at all possible.
• Many pollution accidents could have been avoided if there had been better safety.
• It all could have been avoided if they just, you know, communicated.
• Lengthy transitional periods for certain Member States must be avoided if at all possible.
• Circumstances that could have been avoided if you'd simply removed your brother from New York as I recommended a few months ago. "Simply"?
• The rapporteur believes that this problem could partly be avoided if electricity was produced closer to the main consumption points, whenever it is possible.