Don't come up with such arguments. In the late 1980s, ISRO was developing GSLV configurations with cryogenic upper stages, with a fallback option of imported cryogenic engines/ indigenous liquid fuel stages. A project to develop a 120 kN cryogenic engine was initiated in 1986 & a subscale 10kN engine was tested in 1987. Later when Glavkosmos agreed to provide the cryogenic engine (originally developed for their moon mission)& stage with technology transfer, the indigenous cryogenic engine project was cancelled.
Later we were denied the technology we were forced to come up with an engine similar in form, fit & function. Our first cryogenic engine, that too one working on staged combustion cycle. I suggest you read up on how difficult staged combustion cycle is.
In the early 2000s, ISRO started developing the LVM3 with the aim of launching 4 tonne class satellites to GTO, they deliberately chose to develop a heavier trust cryogenic engine based on gas generator cycle to cut short the development time. That's enough to prove how difficult CE 7.5 was.
However with the failure of gslv mk2's cryogenic engine in it's 2010 flight, LPSC had to concentrate their efforts & manpower in perfecting the CE 7.5 engine. That's why I said this significantly affected the Indian space program.
So do you think this is some kind of 'Russian assistance' ? If Glavkosmos hadn't offered us the engine or if the technology transfer was actually completed, we would have been at greater heights now.
Anyway if you're talking about perfecting the GSLV, the only thing left to be perfected is the restarting capability. GSLV is largely developed from PSLV having many similar stages.
