2nd and 3rd questions:
2. what do lendl and agassi have in common?
3. and what do they dont have in common as far as slams go?
2. Equal amount of slams for one, eight each. Also both managed almost 50 match wins in all four slams, something of which they were quite alone until recently. Plus US Open were clearly the best slam for both.
3. Agassi won all four on different surfaces, Lendl only three and never on grass. Agassi had a positive stat in finals, winning more than he lost, Lendl did not. Plus Lendl had a great series of consecutive SFs reached and consecutive finals in one slam, Agassi did neither.