This work aims to explore novel ideas and architectures to implement flexible, high-efficiency load modulated amplifiers. A set of versatile closed-form equations, termed VIP equations, is derived for analyzing active N-port networks. These equations are applicable to a wide range of issues, including load modulation (LM) in amplifiers and mutual coupling in multiple-input and multiple-output (MIMO) systems. To illustrate the use of these equations, they are applied to several conventional LM structures such as Doherty and load-modulated balanced amplifier (LMBA), enabling broader design space exploration. To demonstrate how to invent new architectures using VIP equations, a novel load-modulated architecture, termed Tri-Coupled-Line Amplifier (TCLA), featuring a six-port three-coupled-line combiner, is proposed and analyzed. This architecture offers significant advantages, including design flexibility, enhanced back-off efficiency, while maintaining simplicity in design and implementation. The output back-off equation of TCLA is equivalent to conventional Doherty, with efficiency characteristics close to three-way Doherty and Sequential-LMBA (SLMBA), but without the overdrive challenges associated with SLMBA. To concept proof, the TCLA prototype with 45 dBm power at 2.4 GHz and %60 efficiency at 8 dB output back-off (OBO) was designed and implemented