> Almost every materials are stronger against tensile stresses than compressive stresses, and stainless steel is no exception, so an array of mighty Raptors try

> Almost every materials are stronger against tensile stresses than compressive stresses, and stainless steel is no exception, so an array of mighty Raptors trying to compress the booster lengthwise from the bottom, could be, just could be, less ideal than a pair of tip-jets pulling upwards and straightening the shell. Maybe it's less ideal, but SpaceX has almost certainly run the simulations to figure out whether the booster can indeed survive a late-stage launch configuration, and they probably found that the current design is perfectly capable of withstanding the stresses. > So I think there could be potentially some net positive effect in "test firing" the proposed side-jets at launch for few moments Only if you fired them most of the way up. If you only fire them for a few seconds, they're still dead weight for 90%+ of the booster flight, and the extra thrust wouldn't be enough to compensate. > Isn't that going to look even cooler than what it is already? Rocket design is not about looking cool, it's about shaving off as much weight as you can and adding as much thrust as you can. Cool looks are generally an afterthought (in fact, by going for an unpainted stainless steel, SpaceX is saving a lot of weight that would be added if they had to paint the entire thing). SpaceX isn't building to cover ideal microoptimizations in certain parts of flight, they're building the best overall configuration that will work in the specific launch profile that they are targeting.