Infinitive vs. To Be Gerund [duplicate]

Many grammar books claim that ‘see’, ‘hear’, ‘taste’, ‘smell’, ‘feel’ are verbs that aren’t used in continuous forms, and yet, we do hear and see it quite often used by native speakers. For instance, read the title of this article:

Are You Hearing Enough Complaints?

The average complainer tells nine or more others about his unhappy experience. So successfully resolving a complaint is not only likely to generate increased business from the complainer, but also to restore nine or more potentially lost opportunities with other customers or prospects. The point is, if you're not hearing any complaints this might be a reason to worry, rather than to congratulate yourself.

I myself would say "I'm hearing more and more people pronounce this word this way" just as much as I would say "I hear more and more people..."

Your thoughts, native speakers? Does using the continuous form of this verb feel odd to you?

1. Are you hearing that noise?
2. That cake is tasting delicious.
3. You are smelling like a rose.
4. He is seeing the blue sky.

All of the above sentences would be considered as being either ungrammatical or nonstandard English by most prescriptive grammar books. And I would avoid saying these type of phrases myself. Furthermore, it is true that verbs of senses are not normally used in the present progressive but I've never read a grammar book which strictly prohibited their use. Sentences 1 to 4 will sound more natural and "native-like" if the present simple tense is employed.

1. Can you hear that noise?
2. That cake tastes delicious.
3. You smell like a rose.
4. He can see the blue sky.

The verb hear often means we perceive or detect a sound with our ears. It is not a dynamic action but an involuntary one, hence it is classed as being a stative verb. On the other hand, the verb listen expresses intention and is a dynamic verb. Consider:

A: What are you listening to?
B: This great album by [group], I'm always listening to their music.

You couldn't replace listen with hear in that particular context.

To express the concept that a noise is audible with your ears, we often use the modal verb, can in the present tense.

(Three friends on Skype)
A: Can you hear me, now?
B: Yes, I can hear you loud and clear.
C: No, sorry. I can't. It's very difficult to make out what you're saying. The audio's not very good I'm afraid.

Wikipedia confirms and adds

Verbs of mental state, sense perception and similar (know, believe, want, think, see, hear, need, etc.) are generally used without progressive aspect, although some of them can be used in the progressive to imply an ongoing, often temporary situation (I am feeling lonely), or an activity (I am thinking about a problem). (...) In colloquial English it is common to use can see, can hear for the present tense of see, hear, etc.

However, the verb hear also means to receive information by the ear, as Ws2's answer illustrates, and in this case the progressive form can be used e.g.,

• I'm constantly hearing stories about those awful people who've recently moved in the neighbourhood. They say, the son is an ex-convict.
• I am constantly hearing about sugar and how it is truly evil (...).
• This is the first time I'm hearing this.

and in the phrase quoted by the OP

"Are you hearing enough complaints?" = Have you been receiving information recently?

^{Feel in my opinion, does not fit very well in the category of stative verbs. Feel when it is a sense can be used in the progressive form as much as the present simple tense. 1) I'm feeling lazy today (I feel lazy today) 2) How are you feeling? (How do you feel?) 3) He's not feeling too well. (He doesn't feel too well.) BUT 4) What are you doing? I'm feeling this textile (I feel this textile.).}

I can use the continuous tense in the following without any fear of sounding odd: "I'm smelling this milk to see if it's any good", "What are you tasting?"; "The sniffer-dog is smelling all the suitcases for explosives" (as suggested by Ws2); and "I'm seeing Anthony later tonight."

Michael Swan in Practical English Usage gives a list and definition of these stative verbs.

There are many verbs that are not usually used in the progressive tenses and others that are not used in the progressive tenses in certain of their meanings. The most important of these [stative] verbs are:

1. dislike, hate, like, love, prefer, want, wish
2. astonish, impress, please, satisfy, surprise
3. believe, doubt, feel (=have an opinion), guess, imagine, know, mean, realize, recognize, remember, suppose, think (=have an opinion), understand
4. hear, see, measure (=have length etc), taste (=have a flavour), smell (=give out a smell), sound, weigh (= have weight)
5. belong to, concern, consist of, contain, depend on, deserve, fit, include, involve, lack, matter, need, owe, own, possess
6. appear, resemble, seem

So to summarise, it is not true that the verbs, hear, see, taste, etc. are not used in the continuous forms, it depends on context and meaning.

according to English Grammar by E. Istomina, A. Saakyan "The verbs of sense and mental perception (see, hear, understand) are used to express surprise, doubt, disbelief (especially in questions): What am I hearing here? I can't believe what I am seeing! Am I understanding you correctly?