A few disconnected thoughts:

Thrashing around is resisting, and potentially assault. A well informed protester (and they're not uncommon) will go limp.

Those who incite violence at protests in the US are often plants. Sometimes the police plants them, or sometimes its those with interests in what's being protested.

Pepper spray can cause permanent damage http://en.wikipedia.org/wiki/Pepper_spray#Effects

When I get upset about police brutality, it's more often about the system surrounding it than the individual offending officer (although in cases where an officer is a uniquely repeat offender, it becomes harder to have sympathy). Among the problems are: the trend towards the militarization of police; non-lethal weapons are supposed to be a safer stand-in for lethal weapons, but they are used with much less discretion and oversight; courts often give police a mere slap on the wrist when it's determined that there was misconduct; the people who make the decisions to escalate police response often act with politics in mind instead of public safety (I'm talking about protests, not riots or the sort of 1 on 1 standoff shooting sort of scenario).

I was involved in a months-long (years in some ways) series of protests, demonstrations, occupations, etc. Some laws were broken (not be me) and the police was disobeyed. But the one thing I am proud to say about our opposition is that they wanted to proceed in a civil fashion, and because of that nobody got seriously hurt. Some lines were crossed, and some situations were fumbled, but nobody came away with more than minor injuries ~ and those seemed to be more from mild incompetence on behalf of the police rather that any real malice or lapse in judgement. (There was one day where we were more or less threatened by construction workers waving running chainsaws at us, but that was construction workers trying to to a job they weren't trained for. As soon as those in charge got wind of this, police arrived and told those insanely dangerous fuckers to pack it up.)

My point is that I've seen civil disobedience, and police response to it, at its finest. You and I will likely agree on many of those 75% of times where the police officer seemed to have little choice. But for more than 25% of cases, I get the distinct impression that the situation was sorely mismanaged prior to the officer being left with no choice.

/rant

tl;dr I agree. Here's some random thoughts and personal experience. Have an upvote.