They should have outer perimiters setup on the steps/ramps to stop people there who clearly have no tickets/fake tickets
about two hours before kick-off they were checking tickets in the outer perimeter but must've stopped for whatever reason. even then, i just flashed a picture of a random ticket on my phone as i hadn't collected mine yet.
unless it's physically scanning a ticket i don't think that an outer perimeter really does much. just look at Madrid - if you had a blag ticket you'd more than likely get past the first perimeter.
i also thought the new Wembley security contractors (they hired a new company) were worse than previous, weirdly heavy-handed in searches etc i found, although obviously as things got busier it seemed like they lost control a bit.