He doesn't have a real speed advantage to speak off. Base Saber is mach 15 and can dash at mach 45. Her reactions are mach 45 as well. Bleach is somewhere around the mach 15 - 20+ range. GT would not even slow down Excalibur and the whole "charging up" is myth. Saber pretty much used Excalibur while dashing towards Gilgamesh in an instant and the same happened in Fate/Zero when she used it against Rider.
@Fehafare: Well, this profile says mach 14 at her peak.
And no one in Bleach is tanking Excalibur, in other words there isn't a single character right now that can beat her.
No servant can tank yama's bankai so I guess no servant can beat yama.
Btw Monster Aizen's fragor is also calculated to be in the city+ range and Ichigo tanked it without just a few scratches
@supernova7005: The profile is outdated to hell and back (well not that much but still outdated), that's a calc back from the days when they relied on F/HA.
They can actually... not to mention there is Avalon. And she has superior reactions, acts first, one shots.
Saber's Excalibur at it's weakest (the scene in the Fate route when she uses minimal output to one-shot Rider) is well above city level + and not to mention that it can also vaporize and atomize targets making the whole thing with their durability pointless to begin with.
Both of those things are disproved in the VN... it's pretty much two myths like the charging up the people who never touched the VN made up. First of all, in the Fate route Shirou deflects Gil's Ea back at him, forcing him to retreat.
And now explain a bit further on the "can't attack" part. Every Servant has an ability called "Spirit Form" which allows them to turn invisible and intangible. In other words all of them have a mini-Avalon with no cost to it, actually it even reduces the prana consumption. With that in mind, it would be completely retarded to have an EX rank Noble Phantasm that does exactly the same minus the invisibility and it does so for a prana cost as well.
At the end of the Fate route Saber activates Avalon, walks through Gilgamesh's attack and Excaliblasts him at point blank.