Maybe not a bus, but they did play defensively overall, its striking to me that, even United at their best played in a catious way against a sub-par Barcelona.
Though i guess its just a poor match-up for United, they never seem to enjoy playing you, while Chelsea has given you more of a fight.
This!
Barca was a nightmare for SAF's UTD even in their best versions.
They do not park the bus, but the football they play hugely mismatches tiki-taka or let's say in general precise possession football with many short passes and through the center.
The two finals, and the semis of 08 where Barca were better, are proof of that
On the contrary, they could easily sweep the likes of Chelsea of that time, which as you correctly said was the worst match for Barca (always a good bus that sits very deep and has fast and efficient attackers on the counter always gives the worst trouble to Barca)
Had Chelsea go through in that notorious return leg at Stamford Bridge with the Iniesta goal, UTD would have a walk in the park final against them (2nd in a row against a weakened version of that Chelsea) and would have won 2nd CL in a row