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.

{
        return &(*a) < &(*b);
    }
};
struct COrphanTx {
    CTransaction tx;
    NodeId fromPeer;
    int64_t nTimeExpire;
};
map<uint256, COrphanTx> mapOrphanTransactions GUARDED_BY(cs_main);
map<COutPoint, set<map<uint256, COrphanTx>::iterator, IteratorComparator>> mapOrphanTransactionsByPrev GUARDED_BY(cs_main);
void EraseOrphansFor(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
static void CheckBlockIndex(const Consensus::Params& consensusParams);
CScript COINBASE_FLAGS;
const string strMessageMagic = "Bitcoin Signed Message:\n";
namespace {
    struct CBlockIndexWorkComparator
    {
        bool operator()(CBlockIndex *pa, CBlockIndex *pb) const {