in v0.12 https://github.com/bitcoin/bitcoin/pull/7081 (by @luke-jr) was merged adding `-bytespersigop` (with default of 20).

this is preventing simple bare multisig transactions from being accepted into mempool when the size is < 400 bytes.  
eg; https://gist.github.com/rubensayshi/ac4f617207f7a50559e85d61c05800be

from 1-of-7 and onwards they are accepted because the ratio of bytes:sigops is high enough.  
also having 2 or more inputs will work because it again tips the ratio of bytes:sigops over.

the reason mainly being that `GetLegacySigOpCount` calls `GetSigOpCount` with `fAccurate=false`.

It looks like changing `GetLegacySigOpCount` to use `fAccurate=true` would cause side effects in the few other places (`ConnectBlock`, `CheckBlock`, `CreateNewBlock`) and simply adding `fAccurate` as arg to `GetLegacySigOpCount` would affect the value stored in `CTxMemPoolEntry.sigOpCount` which in turn affects a bunch of other things.

{
    fPrintToConsole = GetBoolArg("-printtoconsole", false);
    fLogTimestamps = GetBoolArg("-logtimestamps", DEFAULT_LOGTIMESTAMPS);
    fLogTimeMicros = GetBoolArg("-logtimemicros", DEFAULT_LOGTIMEMICROS);
    fLogIPs = GetBoolArg("-logips", DEFAULT_LOGIPS);
    LogPrintf("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
    LogPrintf("Bitcoin version %s\n", FormatFullVersion());
}
/** Initialize bitcoin.
 *  @pre Parameters should be parsed and config file should be read.
 */
bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
{
    
#ifdef _MSC_VER
    
    _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
    _CrtSetReportFile(_CRT_WARN, CreateFileA("NUL", GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, 0));
#endif
#if _MSC_VER >= 1400
    
    _set_abort_behavior(0, _WRITE_ABORT_MSG | _CALL_REPORTFAULT);
#endif
#ifdef WIN32