I'm sorry but I REALLY don't get the requests for Str-Based it doesn't make ANY sense...Acrobats should be lithe and agile not the Hulk, my only assumption is that it's because Str can be made higher than Dex which is not a good reason.
If anything the tree should be MORE Dex-based and include some abilities reliant on you actively moving.
Here's a Google image search: https://www.google.ca/search?q=acrob...vid=1366926590
Note the lack of hulks...not a single person could be considered more than "fit"
Sidenote: Searching "Thief-Acrobat" mostly just gets generic rogue pictures...bummer.