The speed bleeders are not useless,they are only good for bleeding during regular maintenance. If your bleeding and empty system they are no good. I use them but if it needs a major air bleed I ignore the speed bleed function and just teat them as if they are regular valves.Pump the lever hold,open valve,close valve,release.

Bill. "I spent a lot of money on booze, birds and fast cars. The rest I just squandered." -George Best