It's not only about "parking the bus" and "not parking the bus". Football tactics are a bit more complex than that. In Pedro's peak form (first half of 10/11), he and Villa mostly scored from throughballs inbetween fullback and centerback. Villa's second goal after Messi's throughball in the 5-0 Clasico is an extreme example of what I mean. This happened in 10/11, not 08/09. Another example: Espanyol-Barca 1-5 where Espanyol played a suicidal high line. Again: 10/11, not 08/09. Pedro's main attribute has always been to sneak behind the defensive line, receive a throughball that puts him 1 on 1 with the keeper and score. He rarely scored "individual" goals. Neither Villa nor Pedro ever had to dribble or provide any kind of wingplay. They'd pass it back to the middle and make runs behind the defense. In 2013, this doesn't cut it anymore. We need more from our wingers. Partly because teams block the passing angles and press the most dangerous passers very early (I've seen Ajax pressing Xavi with 3 men in Barca's own half, Messi gets fouled when he's on the ball for longer than 2 seconds). There is a correlation between Xavi's decline of throughballs and Pedro's decline of goals. Partly because of the decline of our possession play (or simply put: Xavi's decline). Partly because teams are now aware of runners from the wings and block the channels. Or in short: Teams don't play Barca in 2013 like they played Barca in 2008, 2009, 2010, 2011 or 2012.
Also people overrate "the old Pedrito". He became important in the second half of 09/10 and formed a deadly duo in the first half of 10/11 with Villa. In the second half of 10/11 he already stopped playing well, until the CL final. Ever since he hasn't been the same. He had a 10 month period at consistent world class level at most and only glimpses here and there ever since. We remember him more fondly because of his many big game goals. But overall he looks like a hardworking, average system player who had a nice run of form. Bit like Ji-Sung Park at Manchester United.
No, I don't think Ajax played like those teams in 08/09. Not even remotely close. Which team in 08/09 would be so brave and put so much pressure on Barca as Ajax did? In the entire Pep era I only remember Real Betis playing like that and we never did well against them, especially not away from home. In a similar scenario like yesterday where we missed 5 or 6 starters, Betis beat us 3-1.