I agree with you on some points but not all. Yes, colleges do not care where you are seen. They want the best talent and wherever they can find it and sign it they'll take it! But I do think that showcases are beneficial to kids who are not blue chip recruits. And I totally disagree about you saying travel is a rip off. Thats based on where you spend your money and who you put your faith in as a parent putting your child in a travel program and its also your responsibility to pick the right travel orginazation for your son. And my take on where kids are seen is really in the summer when the scouts have the time to go out and see games as their season is not in. But, most definetelty you can be seen in either one. I feel it is easier to be seen in the summer.
Now, I am 100% with you that there are terrible coaches in travel and HS and also amazing coaches in travel and HS. Also, I feel development is CRUCIAL! But, in my opinion I feel I developed with my travel team. In my HS season, we don't have advanced approaches and do not really make tweaks or changes. Its really just practice. With my travel we have a indoor facility where we can swing, throw pens, take ground balls and run and we get the instruction that is necessary for us to improve. We learned with the same head coach who taught us the game and how to play it the right way since we were little (which goes with you LL quote which I agree with) and we have ex D1 players and coaches who are always in our facility helping out and coaching us up (which also aids when getting recruited as these guys all have connections in the coaching realm) I will say that this may sound (a lot) biased towards travel because my HS coaching staff is filled with a teachers aid who lives at home with his mom and two social studies teachers who one played in college (HC) and another who has a "How to play outfield for Dummies" book in the back seat of his car.
Also, I agree with limited fall ball.
Sorry I wrote so much!