There are tens of questions here on EL&U about the grammaticality of the try and do something construction and its merits compared with the unremarkable try to do something collocation.
However, this question is not related to those in any way. This question is about the grammatical constraints on the use of the try and do something construction.
This morning whilst on a coffee break I realised that the try and do something construction, henceforth referred to as tryand for short, is not a ready replacement for try to do something. So far these are the grammatical constraints that I have noticed:
- Tryand is restricted to the present tense only:
- I try and visit once a week.
- *I tried and visited once a week. (ungrammatical with this meaning)
- *I tried and visit once a week. (ungrammatical with this meaning)
I put the two ungrammatical versions there, because it is not clear whether the second verb in the tryand construction is usually present tense or plain form (aka an infinitive).
When occurring in the present tense, tryand cannot be used in the third person singular:
- I try and visit them.
- You (all) try and visit them.
- *He tries and visit them. (ungrammatical)
- *She tries and visits them. (ungrammatical)
- They try and visit them.
Tryand is useable as the complement of other present tense verbs without the third person restriction, or any past time reference restriction:
- You can try and visit them
- He can try and visit them
- He would try and visit them
There is also no restriction on either the third person or the use of the past simple if the auxiliary do is used:
- She does try and visit every week.
- She did try and visit them as often as possible though.
This does not work with the perfect auxiliary have where there seems to be a bar on past time reference:
- *She has tried and visit them as often as possible (odd or ungrammatical)
- *She has tried and visited them as often as possible (ungrammatical with this meaning)
So, what I have drawn from this is that perhaps tryand cannot be used in any construction where the second verb would have to be inflected.
My questions are the following:
Are there any further restrictions on the use of tryand which I have missed?
When the verb try in the tryand construction is present tense, is the second verb also present tense or is it a plain form of the verb (an infinitive)?
Why exactly does tryand have these restrictions?
Answers to any or all of the questions above would be welcome.
You may add interaction with negation to your list of restrictions.
The second verb is in the plain form, as is evident when we test with be: We always try and be/*are helpful.
One property to add to your list of restrictions is interaction with negation.
There is an extensive discussion of try and in Webster’s Dictionary of English Usage, where, in addition to some of the restrictions you have already listed, they also note the following:
A negative may precede try and, but if a negative follows try, to is used:
… when you are on your moorings, don’t try and get into her—Peter Heaton, Cruising, 1952
Not to try and keep either a diary or careful income tax records —And More by Andy Rooney, 1982
Try not to take her out shopping —nurse quoted in McCall’s, March 1971
The second verb is in the plain form
Here is the relevant discussion from CGEL (p. 1302), which includes some other interesting observations.
(b) Try/be sure and V
 PLAIN FORM + PLAIN FORM PLAIN PRESENT + PLAIN FORM
i a. Try and not be so touchy. b. We always try and do our best. [try]
ii a. Be sure and lock up. b. [not possible] [be sure]
This is very different, semantically and syntactically, from the ordinary use of and. Note first that, unlike the clausal coordination We always try and we do our best, [ib] does not entail that we do our best. Secondly, this idiomatic construction is syntactically restricted so that and must immediately follow the lexical base try; this means that there can be no inflectional suffix and no adjuncts: She always tries and does her best and We try hard and do our best can only be ordinary coordinations. There are two forms that consist simply of the lexical base: the plain form, as in [ia], and the plain present tense, as in [ib]. But the verb following and is always a plain form, as is evident when we test with be: We always try and be/*are helpful. In spite of the and, therefore, this construction is subordinative, not coordinative: and introduces a non-finite complement of try. And can be replaced by the infinitival marker to, and being slightly more informal than to. Be sure works in the same way as try, except that the lexical base of be is only the plain form, so this time there is no plain present tense matching [ib]: We are always sure and do our best is not possible as an example of this construction (and unlikely as an ordinary coordination). Because the construction is subordinative, the across the board restriction does not apply: This is something [that you must try/be sure and remedy].
Other constructions in which and replaces a possible to
Relevant to your discussion with John Lawler, Webster’s Dictionary of English Usage also says that
Quite a few commentators lump try and with other constructions in which and replaces a possible to. Go and is the oldest of these, dating back to the 13th century. It has always been respectable in speech and casual writing… Unlike try and, go and can be inflected, as in these constructions: … and he went and sat on a stone —Kay Cicellis, Encounter, March 1955… Come and is also old, and equally respectable… Be sure and is also frequently encountered.
There are a few other verbs that turn up with and where to could have been used:
He didn’t have to stop and think about his answer—Elmer Davis, But We Were Born Free, 1954
And you can tell your daddy that someday I’ll be President of this country. You watch and see —Lyndon B. Johnson, quoted in Sam Houston Johnson,
My Brother Lyndon, 1970
If you want to write, start and write down your thoughts —Leacock 1943
They also mention take and (Homer was courting a second time to get him a good wife and a home-keeper for his children, when he took and fell off the church-house roof —Maristan Chapman, The Happy Mountain, 1928)
The Columbia Guide to Standard American English also mentions up and (He up(ped) and punched me in the nose).