As segwit is active on testnet, blocks will only be downloaded from NODE_WITNESS peers. Though, exactly those peers are disconnected after `BLOCK_STALLING_TIMEOUT = 2` seconds. I am running master (6e6ab2c)

This behavior is consistent across restarts. Sample [debug.log](http://pastebin.ubuntu.com/23058327/) and [getchaintips](http://pastebin.ubuntu.com/23058325/).

It is possible that I shot my own foot at some point, but it seemed smelly enough to create an issue.

if (pto->vAddrToSend.capacity() > 40)
                pto->vAddrToSend.shrink_to_fit();
        }
        CNodeState &state = *State(pto->GetId());
        if (state.fShouldBan) {
            if (pto->fWhitelisted)
                LogPrintf("Warning: not punishing whitelisted peer %s!\n", pto->addr.ToString());
            else {
                pto->fDisconnect = true;
                if (pto->addr.IsLocal())
                    LogPrintf("Warning: not banning local peer %s!\n", pto->addr.ToString());
                else
                {
                    CNode::Ban(pto->addr, BanReasonNodeMisbehaving);
                }
            }
            state.fShouldBan = false;
        }
        BOOST_FOREACH(const CBlockReject& reject, state.rejects)
            pto->PushMessage(NetMsgType::REJECT, (string)NetMsgType::BLOCK, reject.chRejectCode, reject.strRejectReason, reject.hashBlock);
        state.rejects.clear();
        
        if (pindexBestHeader == NULL)
            pindexBestHeader = chainActive.Tip();
        bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->fOneShot); 
        if (!state.fSyncStarted && !pto->fClient && !fImporting && !fReindex) {
            
            if ((nSyncStarted == 0 && fFetch) || pindexBestHeader->GetBlockTime() > GetAdjustedTime() - 24 * 60 * 60) {
                state.fSyncStarted = true;