As above, beyond the rampant Laconophilia of most history and media, how effective was the Spartan "Agoge" method of training at producing soldiers that were effective at taking objectives, besieging cities, and winning victories in open battle? More strictly, I am interested in the effectiveness of the Agoge as a training method, not simply a list of Spartan victories. Were there any noticeable deficits in the training, or weaknesses in it that allowed Spartan losses in battle? Would a similar method of training produce effective soldiers for a modern battlefield?(asking for reasons of a story I am working on)
Thank you for any answer.
Here's a slight wrinkle: To fully understand the Spartan prowess in warfare, you have to understand the cultural context in which it takes place in, that being an environment of deliberate amateurism in military affairs. A snappy way to sum up Spartan proficiency in warfare is that saying, "In the land of the blind, the one-eyed man is king". To further examine this matter, we turn as always to the inestimable u/Iphikrates. This three-part writeup examines Sparta's reputation versus its actual performance in the field.
As for the agoge...well, to be rather blunt, the answer to all your questions is "No" because the agoge, and indeed the entire Spartan system, are not set up to do any of the things as listed. The Spartans did not train to fight.
For further information and more than you ever wanted to know about Classical Greek warfare, I highly commend the good Doctor's flair profile
"tl;dr: you're a Spartan, your life is shit" - Iphikrates