redis-rb, EventMachine::Synchrony::ConnectionPool and pipelined command

gistfile1.rb

require 'benchmark'
require 'redis/connection/synchrony'
require 'redis/connection/hiredis'
require 'redis'

redis = EventMachine::Synchrony::ConnectionPool.new(size: 1) do
  Redis.new(:password => 'my password',
                  :host => 'my host',
                  :port => my port)
end

time = Benchmark.realtime {
  redis.hincrby(:hash, :counter, 2);
  redis.hset(:hash, :field, 'value');
}
puts "#{time*1000} milliseconds"

/*This code does not work*/
time = Benchmark.realtime {
  redis.pipelined {
    redis.hincrby(:hash, :counter, 2);
    redis.hset(:hash, :field, 'value');
  }
}
/*This code works*/
time = Benchmark.realtime {
  redis.execute(false) do |redisX|
    redisX.pipelined {
      redisX.hgetall(:hash)
      redisX.hincrby(:hash, :counter, 2);
      redisX.hset(:hash, :field, 'value2');
    }
  end
}
puts "#{time*1000} milliseconds"