The 'connection.pool.group.maxConnections' determines the maximum connections to a Data Warehouse (i.e., the total connections to all SQL Engines in the warehouse).
The 'connection.pool.user.maxConnections' determines the maximum connections a single user on a single SQL Engine will have. This is intended to prevent a single user from monopolizing all the group connections. However, it only applies when we open links for specific users (i.e., delegation/impersonation) and not to the general case.
Most customers don't need to worry about this setting. If you don't have impersonation/delegation, `connection.pool.user.maxConnections` has no effect.