So my boss tells me that industry standard for serving images is that you have one image on the server that is approximately 3x larger than the largest size you need it to be and resize it on the client side as you need. However, a lot of the tutorials I have seen online lead me to believe that is not true. Is it? Because I have to serve up a whole lot of 150kb images for something I didn't even want to do in the first place and it's causing serious performance issues, even with lazy loading.