The blade always givers me the shivers, I usually opt for the good old credit card, the lighter the colour the easier to see the algae in front.. If you can get a lending hand in to follow up with a suction pipe behind, that's also great. My new most rewarding method is to gently move back the gravel where I can or in stages and then let my young ancistrus brigade have a party, the next morning the glass is crystal clear..
I breed and rotate a cleaning squad of about 30 to 40 veil ancistrus in my big planted tank, when they reach 50mm they go to the LPS and make way for the latest batch. I find they are more efficient cleaners and can get into smaller places when they are a younger age and size..