The High Sparrow is a little bird

[The Fresh PtwP]

At first I thought the High Sparrow was more or less who he seemed, a religious nutjob raised up by the masses then on my reread i found a couple gems that changed my mind:

"The eunuch had agents and informers all over the city. It would have been a simple matter to have Tyrek snatched during the confusion...provided he knew beforehand that the mob was like to riot." Jaime, AFFC

Not much on it's own but it is the best quote of many to show Varys influence over "the mob". The same mob that raised the High Sparrow up.

Then we have this from the HS:

Cersei "You have not come."

HS "The hour is not yet ripe."

...

"The realm is full of kings. For the Faith to exalt one above the rest we must be certain" 

He then goes on to give Cersei a brief Aegon themed history lesson...but wait a minute! The hour is not yet ripe sounds an awful lot like:

"Too soon, too soon...what good is war now? Delay."

Makes me think we are no longer talking about Tommen, who was never going to get that blessing.

Another thing that caught my attention is Lemore and admittedly speculation. I understand the reasoning for her being on the poleboat. A king should know the religion of the people he's about to be ruling etc...but honestly a couple books could've sufficed, unless the people above Aegon know a religious fanatic is going to hold some sway in KL, Lemore seems like overkill. 

Which leads me to believe this has been in the works for a while, either the HS is in league with Varys or Varys manipulation of the small folk "birthed" the High Sparrow.

Lastly some wordplay, a sparrow is literally a little bird. Or as the High Sparrow told Brienne and Cersei 

"The sparrow is the humblest and most common of birds, as we are the humblest and most common of men."

[The Hoare]

Makes sense.

The HS is famous among the lowborn, which would be a great help to the cause of Aegon

[Red Man Racey]

Reading the title I thought you were suggesting that the High Sparrow is a former "little bird" of Varys' spy ring - glad I was wrong about that. I'll have to go back and read through looking for clues on this theory, but at face value I can see the High Sparrow and Varys being in leage with one another. His rise to the head of the church always did seem fishy, as if he had help from somewhere or at least a hidden agenda or something.