There are several use-cases which require the usage of a custom ILcdOWSTransport. For example:

Configuring the custom transport on the model decoder

When you want to visualize WMTS data on a map, you first use the WMTS model decoder to create an ILcdModel, as illustrated in Visualize WMTS data on a Lightspeed map tutorial.

You can pass the custom transport to the constructor of the model decoder, and the model decoder will use this transport: 

TLcdWMTSModelDecoder modelDecoder = new TLcdWMTSModelDecoder(customTransport);

Configuring the custom transport on the TLcdWMTSClient

When you want to send your own WMTS requests to the server, you use the TLcdWMTSClient directly. Creating a client which uses a custom transport is done by passing the transport to the constructor: 

TLcdWMTSClient client = new TLcdWMTSClient(serverURI, customTransport);