Yeah I was quite critical of the ION when it first opened because of these slow turns. At the time I didn't understand why they went with that design since, for a little bit more money they could have eliminated the bottleneck. What I came to learn is that the Region of Waterloo was operating on a shoe-string budget when they built ION because unlike Toronto, Ottawa, Hamilton, and Peel who had their LRTs paid for in full by daddy Provincial and/or Federal government, the Region of Waterloo only got 2/3rds of the funding from upper government and had to fund the rest themselves. With only 500,000-ish residents between the tri-cities (rural townships didn't pay for ION) there wasn't the kind of tax base available to do everything perfectly, so some compromises were required. A lot of the strange turns on ION were put in to reduce land acquisition costs. The Region of Waterloo wanted to use their own rights-of-way as much as possible, which wasn't too difficult as they own most of the rail spur lines which intersect the city (Iron Horse Trail ROW), but they had to use roads in some areas to link the rights-of-way together. Honestly, for a total construction cost of less than $1 billion, for the area served and the speeds provided, the ION is probably the best value-for-money transit project in the country.
With Stage 2 they're going to be more liberal with the construction costs, so there will be fewer of these bottlenecks. Not to mention based on the way ION is designed, if they ever wanted to re-route things to get rid of turns, it would be easy to do so.