Jumpman16
np: Michael Jackson - "Mon in the Mirror" (DW mix)
No, a 236 speed Zapdos with Blissey out of the way and a few CMs under its belt works in practice as well, not just in theory. And as stated, it doesn't really matter if the opponent knows what kind of Espeon it is if you're taking out one of the biggest threats to the strategy in Blissey and Sand Stream.Theoretically it would help, but it needs speed. After one BP the opponent knows the Espeon is an Espyjump. So why not try to get the most out of the first BP?
Also, you're forgetting what you said about Scarf pokemon being a problem. What is a 328 Speed and 383 SpA Zapdos going to do about a ~450 Speed Scarfchomp that a 236 Speed one can't? The main answer was alluded to in a prior post of mine and is a direct answer to your "Why have a bold zapdos if you're going to sweep with it?" that you probably thought was rhetorical:
Adamant, 394 Atk Garchomp's Choice Scarf Outrage on a 384HP/287Def (max/near-max) Zapdos: (69-81%)
Adamant, 394 Atk Garchomp's Choice Scarf Outrage on a 322HP/206Def (4EVs/min) Zapdos: (115-135%)
Adamant, 383 Atk Heracross's Choice Scarf Stone Edge on a 384HP/287Def (max/near-max) Zapdos: (50-59%)
Adamant, 383 Atk Heracross's Choice Scarf Stone Edge on a 322HP/206Def (4EVs/min) Zapdos: (83-98%)
Adamant, 394 Machamp's Choice Scarf Stone Edge on a 384HP/287Def (max/near-max) Zapdos: (51-61%)
Adamant, 394 Machamp's Choice Scarf Stone Edge on a 322HP/206Def (4EVs/min) Zapdos: (85-100%)
Now, you didn't actually say you'd use a 322HP/206Def Zapdos with 383SpA/328Spd, but I hope you now see why defensive EVs are going to enable it to sweep more than Speed EVs would.