About Oscilloscope Probing Philosophy
I am a user of Agilent MSO oscilloscopes. I had never heard about anything like "probing philosophy" before you showed me this document. But I have heard much about "signal measurement techniques".

In short, this document is about marketing rubbish, as you (probably) know that Tektronix and Agilent compete for the market and Tek comes after Agilent here. I will not advocate any of them, they both provide good, state-of-the-art products, but the use of a "compare to the leader" method in a market competition is generally used by the one following the leader, not by the leader itself.

Look for yourself, the document discusses the "probe bandwidth", saying nothing about the components from which that bandwidth results, i.e. capacitance (I found no mention of the "pF" unit in the whole doc) in the first place. There are no physics, only claims in the doc.

The Agilent o-scopes I'm familiar with, have internal switches to select between 10 Megs and 50 Ohms input resistance while input capacitance is mostly a property of a passive probe. There are also active probes to make HF/VHF measurements better/possible.

What to use depends on the appropriate signal measuring technique which, in turn, depends on the situation you are facing. There is no instrumentation task that can be done with Tek while not with Agilent, and vice versa, of course.

Therefore, such "philosophy" is about marketing [rubbish], not electronics [truth :-].

P.S. Also, there is Agilent's answer for Tektronix's question on the philosophy.