Does anyone know what the angled grooves on both the frame underside and top of slide are for? Are they just for looks, or do they serve a purpose?

Let me venture forth with a SWAG. Being that the Model 41 is a blowback operated semi-auto, hot gases and powder residue is vented back towards the shooter as soon as the empty case clears the chamber. The angled grooves are there to cause disturbances in the gas flow forcing the gas and debris to vent away from the shooter. Doubt if S&W put the grooves in for cosmetic purposes. Best source to check with is the S&W site. Bet they know. ;)

Thanks! That sounds logical enough. There is an open path back to the shooter when the slide is in recoil.

On the grip, they are for a more secure purchase, on top of the slide they reduce glare